THE  UNIVERSITY 


OF  ILLNIOIS 


LIBRARY 


1e 


NOTICE:  Return  or  renew  all  Library  Materialsl  The  Minimum  Fee  for 
each  Lost  Book  Is  $50.00. 


The  person  charging  this  material  is  responsible  for 
its  return  to  the  library  from  which  it  was  withdrawn 
on  or  before  the  Latest  Date  stamped  below. 

Theft,  mutilation,  and  underlining  of  books  are  reasons  for  discipli- 
nary action  and  may  result  in  dismissal  from  the  University. 
To  renew  call  Telephone  Center,  333-8400 

UNIVERSITY   OF   ILLINOIS   LIBRARY  AT  URBANA-CHAMPAIGN 


AUG  2  4  1390 


MAR 


0  1  2! 


20  m 


L161— O-1096 


Issued  April  21,  1911. 

U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ANIMAL  INDUSTRY.— Bulletin  134. 


A.  D.  MELVIN,  Chief  of  Bureau. 


THE  ESTIMATION  OF  TOTAL  SOLIDS  IN 
MILK  BY  THE  USE  OF  FORMULAS. 


BY 

R.  H.  SHAW, 

Dairy  Chemist^  Dairy  Division, 
AND 

C.  H.  ECKLES, 

Professor  of  Dairy  Husbandry,  University  of  Missouri. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE, 


THE  BUREAU  OF  ANIMAL  INDUSTRY. 


Chief:  A.  D.  Melvin. 

Assistant  Chief:  A.  M.  Farrington. 

Chief  Clerk:  Charles  C.  Carroll. 

Animal  Husbandry  Division:  George  M.  Hommel,  chief. 
Biochemic  Division:  M.  Dorset,  chief. 
Dairy  Division:  B.  H.  Rawl,  chief. 

Inspection  Division:  Rice  P.  Steddom,  chief;  R.  A.  Ramsay,  Morris  Wooden, 
and  Albert  E.  Behnke,  associate  chiefs. 

Pathological  Division:  John  R.  Mohler,  chief. 
Quarantine  Division:  Richard  W.  Hickman,  chief. 
Zoological  Division:  B.  H.  Ransom,  chief. 
Experiment  Station:  E.  C.  Schroeder,  superintendent. 
Editor:  James  M.  Pickens. 

DAIRY  DIVISION. 

B.  H.  Rawl,  Chief 

Helmer  Rabild,  in  charge  of  Dairy  Farming  Investigations. 

S.  C.  Thompson,  in  charge  of  Dairy  Manufacturing  Investigations. 

L.  A.  Rogers,  in  charge  of  Research  Laboratories. 

George  M.  Whitaker,  in  charge  of  Market  Milk  Investigations. 

Robert  McAdam,  in  charge  of  Renovated  Butter  Inspection. 

2 


LETTER  OF  TRANSMITTAL. 


U.  S.  Department  of  Agriculture, 

Bureau  of  Animal  Industry, 
Washington,  D.  C,  November  26,  1910. 

Sir:  I  have  the  honor  to  transmit  herewith,  and  to  recommend  for 
publication  in  the  bulletin  series  of  this  bureau,  a  manuscript  entitled 
'^The  Estimation  of  Total  Solids  in  Milk  by  the  Use  of  Formulas," 
by  R.  H.  Shaw,  of  the  Dairy  Division  of  this  bureau,  and  C.  H.  Eckles, 
of  the  Missouri  Agricultural  Experiment  Station.  The  experimental 
work  herein  described  forms  a  part  of  the  investigations  concerning 
milk  which  are  being  conducted  at  the  Missouri  station  in  cooper- 
ation with  thi^  bureau. 

Owing  to  the  necessity  for  some  more  rapid  method  of  calculating 
the  solids  in  milk  than  the  usual  laboratory  procedure,  the  estimation 
of  these  constituents  by  means  of  formulas  has  been  a  common  dairy 
practice  for  some  years;  and  while  a  certain  amount  of  error  was 
known  to  exist  in  such  calculations,  it  was  assumed  to  be  small 
enough  to  be  negligible  for  most  practical  purposes.  Inasmuch,  how- 
ever, as  a  number  of  formulas  are  in  use,  each  differing  slightly  in 
results  from  the  others,  it  became  a  question  of  some  importance  to 
determine  which  of  them  was  the  most  accurate. 

With  the  object  of  solving  this  problem  the  authors  have  made 
searching  tests  under  exacting  conditions  of  several  of  the  best  known 
formulas,  and  have  in  addition  devised  an  improved  lactometer 
which,  with  a  table  based  upon  the  results  of  the  work  described  in 
this  bulletin,  is  believed  to  furnish  a  method  which  is  more  nearly 
accurate  than  any  at  present  in  use. 
Respectfully, 

A.  D.  Melvin, 

Chief  of  Bureau, 

Hon.  James  Wilson, 

Sea-etary  of  Agriculture. 

3 


CONTENTS. 


Page. 

Introduction   5 

Synopsis  of  formulas  in  vogue   6 

Experiments  to  compare  the  accuracy  of  existing  formulas   7 

Methods  of  calculation  and  terminology   8 

Method  of  sampling   8 

Method  of  determining  specific  gravity  and  total  solids   9 

Comparison  of  the  formulas  with  gravimetrically  determined  results   9 

The  specific  gravity  of  milk  solids   11 

Experiments  to  determine  accuracy  of  lactometers   15 

Tests  of  Babcock  formula  and  new  lactometer  with  individual  milkings   17 

Effect  of  temperature  on  specific  gravity  of  milk   19 

Recknagel 's  phenomenon    20 

How  to  use  the  modified  lactometer  and  table   21 

Method   21 

Directions  for  using  the  table   22 

Summary  and  conclusions   25 

Appendix   26 


ILLUSTRATION. 


Page. 

Fig.  1.  Lactometer  designed  for  use  in  experimental  work   16 

4 


THE  ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK  BY  THE 
USE  OF  FORMULAS. 


INTRODUgTION. 

Various  formulas  have  been  in  use  for  a  number  of  years  as  a 
means  of  determining  the  total  solids  in  milk  when  the  specific 
gravity  and  percentage  of  fat  are  known.  This  rapid  estimation  of 
the  total  soUds  is  a  useful  and  convenient  method  for  purposes  where 
exactness  is  not  required.  Among  the  more  common  uses  that  have 
been  made  of  this  method  is  the  preliminary  examination  of  market 
milk  by  inspectors  and  the  detection  of  adulterations  at  cheese 
factories. 

Recently  certain  organizations  representing  the  dairy  breeds  of 
cattle  have  considered  the  advisability  of  reporting  the  percentage 
of  total  solids  as  well  as  of  fat  in  makiag  official  tests  of  individual 
cows.  It  therefore  became  a  question  as  to  whether  the  determina- 
tion of  the  total  solids  by  means  of  the  formulas  and  the  instruments 
in  common  use  for  finding  the  specific  gravity  was  feasible  and  accu- 
rate enough. 

In  view  of  this  question  Mr.  Ed.  H.  Webster,  then  Chief  of  the 
Dairy  Division  of  the  Bureau  of  Animal  Industry,  requested  the 
authors  to  take  up  the  problem  with  the  view  of  testing  the  accuracy 
of  the  estimation  of  total  solids  by  the  several  formulas  in  common 
use  and  to  suggest  improvements  looking  toward  greater  accuracy 
in  finding  the  specific  gravity  without  making  the  determination 
impracticable  for  use  by  such  men  as  usually  have  charge  of  official 
testing. 

For  the  present  purpose  milk  may  be  regarded  as  composed  of  fat 
and  milk  plasma,  the  latter  being  made  up  of  water  and  the  various 
milk  solids  not  fat,  such  as  the  proteins,  sugar,  ash,  and  other  solids. 
Fat,  having  a  specific  gravity  less  than  water,  has  the  effect  of  lower- 
ing the  specific  gravity  of  milk,  while  the  plasma  solids,  having  a 
specific  gravity  greater  than  water,  have  the  effect  of  raising  it.  It 
is  clear,  then,  that  a  relation  exists  between  the  specific  gravity  of 
milk  and  its  percentage  of  fat  and  solids  not  fat.  The  various  for- 
mulas for  calculating  total  solids  or  solids  not  fat,  when  the  other 
two  factors  are  given,  are  based  upon  this  relation. 

It  is  not  the  purpose  of  this  bulletin  to  bring  out  a  new  formula 
or  to  suggest  modifications  or  revisions  of  those  already  in  use.  -  The 

5 


6 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


main  objects  of  the  investigation  herein  reported  were:  (1)  To  com- 
pare the  percentages  of  total  soHds  calculated  by  means  of  certain 
formulas  in  general  use  with  those  obtained  gravimetrically  in  the 
laboratory;  (2)  to  test  under  more  exacting  conditions  the  formula 
which  yields  results  closest  to  gravimetrically  determined  total 
solids,  and  (3)  to  devise  a  new  or  modify  an  exis^ting  lactometer  with 
which  the  specific  gravity  may  be  more  accurately  determined. 

The  authors  desire  to  acknowledge  their  indebtedness  to  A.  E. 
Perldns  and  G.  C.  Payne,  of  the  Dairy  Division  and  Missouri  Agri- 
cultural Experiment  Station,  for  assistance  rendered  in  obtaining 
the  data  included  in  this  bulletin. 

SYNOPSIS  OF  FORMULAS  IN  VOGUE. 

Behrend  and  Morgen  ^  published  in  1879  the  first  formula  of  which 
there  is  an}^  record  which  attempts  the  calculation  of  total  solids  from 
the  specific  gravity  and  the  percentage  of  fat.  They  were  closely 
followed  in  the  same  year  by  Clausnitzer  and  A.  Mayer,^  who  pub- 
lished another  formula.  These  two  formulas  were,  however,  based 
on  inaccurate  data  and  have  since  been  abandoned.  Since  that  time 
numerous  other  formulas  have  been  proposed,  among  them  being 
one  by  Fleischmann  and  Morgen.^  In  this  formula  the  specific 
gravity  of  butter  fat  was  assumed  to  be  0.94.  This  was  changed  to 
0.93  by  Fleischmann,^  and  the  formula  thus  revised  is  still  in  general 
use  and  is  one  of  those  compared  in  this  investigation.  Hehner's  ^ 
formula  appeared  in  1882,  that  of  Halenke  and  Moeslinger  ^  in  1886. 
and  that  of  Hehner  and  Richmond '  in  1888.  The  latter  formula 
was  revised  in  1894  b}^  Richmond,^  and  the  revised  form  is  known 
as  Richmond's  new  formula.  Babcock  ^  published  his  formula  in 
1891,  but  changed  it  four  years  later. 

Comparisons  of  the  various  formulas  with  gravimetrically  deter- 
mined total  solids  have  appeared  from  time  to  time.  Such  compari- 
sons were  made  in  1889  by  Woll,"  who  worked  with  the  Fleischmann 
and  the  Hehner  and  Richmond  formulas.  In  his  conclusions,  which 
are  in  favor  of  the  Fleischmann  formula,  he  states  that  it  may 

1  Journal  fiir  Landwirtschaft,  Band  27,  p.  249.  Berlin,  1879. 

2  Forschunfjen  auf  dem  Gebiete  der  Vieh-haltung  und  ihrer  Erzeugnisse,  p.  2G5.    Bremen,  1879. 
8  Journal  fiir  Landwirtschaft,  Band  30,  p.  293.   Berlin,  1882. 

4  Journal  fiir  Landwirtschaft,  Band  33,  p.  251.   Berlin,  1885. 

5  Analyst,  Vol.  VII,  p.  129.   London,  1882. 

fiChemiker-Zeitung,  Jahrg.  10,  semester  1,  Chemisehes  Repertorium,  p.  8.   Cothen,  1886. 

7  Analyst,  vol.  13,  p.  26.   London,  1888. 

8  Proceedings  of  the  Eleventh  Aimual  Convention  of  the  Association  of  Official  Agricultural  Chemists, 
Washington,  D.  C,  Aug.  23-25,  1894,  United  States  Department  of  Agriculture,  Bureau  of  Chemistry* 
Bulletin  43,  p.  181. 

» Eighth  Annual  Report  of  Wisconsin  Agiicultural  Experiment  Station,  1891,  p.  292.   Madison,  1892. 

10  Twelfth  Annual  Report  of  Wisconsin  Agricultural  Experiment  Station,  1895,  p.  120.   Madison,  1896. 

11  Agricultuial  Science,  voL  3,  p.  129.   State  College,  Pa.,  1889. 


EXPERIMENTS  WITH  EXISTING  FORMULAS. 


7 


be  used  to  advantage  for  calculation  of  total  solids  if  the  specific 
gravity  of  milk  is  taken  at  15°  C. 

In  the  early  nineties  the  Association  of  Official  Agricultural 
Chemists  made  some  comparisons  of  the  Fleischmann,  the  Hehner  and 
Richmond,  the  Babcock  (original),  and  the  Richmond  formulas. 
Their  results  are  published  in  the  proceedings  of  their  tenth  ^  and 
eleventh  ^  annual  conventions,  and  in  commenting  on  the  same  they 
state  that  the  Hehner  and  Richmond  formula  gave  figures  which 
compared  best  with  those  obtained  gravimetrically. 

EXPERIMENTS   TO  COMPARE  THE  ACCURACY  OF  EXISTING 

FORMULAS. 

In  a  cooperative  experiment  between  the  Missouri  Agricultural 
Experiment  Station  and  the  Dairy  Division  of  the  Bureau  of  Animal 
Industry,  United  States  Department  of  Agriculture,  a  study  was 
made  of  the  changes  in  chemical  composition  which  milk  undergoes 
during  the  natural  period  of  lactation.  Among  many  other  factors 
the  specific  gravity  and  the  percentages  of  fat  and  total  solids  were 
determined  under  controlled  conditions.  These  determinations  were 
made  on  12  animals  through  one  entire  lactation  period,  and  on  2 
of  the  animals  through  two  entire  lactation  periods.  Having  these 
data  at  hand,  it  became  purely  a  matter  of  substitution  to  apply  the 
figures  obtained  for  the  specific  gravities  and  the  percentages  of  fat 
in  some  of  the  most  frequently  used  formulas  for  determining  total 
solids  when  these  two  factors  are  known,  and  comparing  the  figures 
so  obtained  with  the  corresponding  percentages  of  total  solids  deter- 
mined gravimetrically.  As  stated  in  the  introduction,  several 
formulas  have  been  published,  but  perhaps  of  these  the  four  most  used 
are  those  derived  by  Babcock  (revised),  Hehner  and  Richmond,^ 
Richmond,  and  Fleischmann.  In  the  general  lactation  experiment 
above  referred  to  the  samples  were  taken  from  the  very  beginning  of 
the  lactation  period  to  the  very  end  of  the  period,  but  since  the  pur- 
pose of  this  investigation  is  to  show  the  application  of  various 
formulas  in  determining  total  solids  in  normal  milk,  it  was  thought 
best  to  exclude  the  extremes  from  the  comparisons,  and  so  the  figures, 
except  when  otherwise  stated,  refer  to  milk  of  normal  composition. 

The  12  animals  used  in  the  investigation  included  3  each  of  4 
breeds — Holstein-Friesian,  Jersey,  Ayrshire,  and  Shorthorn.  Accord- 
ing to  the  general  plan  these  animals  were  kept  on  a  uniform  ration 

1  Proceedings  of  the  Tenth  Annual  Convention  of  the  Association  of  Official  Agricultural  Chemists, 
Chicago,  Aug.  24-26,  1893.   U.  S.  Department  of  Agriculture,  Bureau  of  Chemistry,  Bulletin  38,  p.  107. 

2  Proceedings  of  the  Eleventh  Annual  Convention  of  the  Association  of  Official  Agricultui'al  Chemists, 
Washington,  D.  C,  Aug.  23-25,  1894.  U.  S.  Department  of  Agriculture,  Bureau  of  Chemistry,  Bulletin 
43,  p.  182. 

3  The  formula  of  Hehner  and  Richmond  was  compared  in  the  same  way  as  the  others,  but  the  results 
were  so  nearly  identical  with  those  of  the  Babcock  formula  that  it  was  thought  best  to  omit  them  from 
this  bulletin. 


8 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


throughout  the  entire  milking  period  in  order  to  eUminate  possible 
changes  in  the  composition  of  the  milk  due  to  feed.  This  ration  con- 
sisted of  alfalfa  hay,  three-fifths,  the  other  two-fifths  being  made  up 
of  corn  8  parts,  bran  1  part,  and  oats  1  part.  The  ratio  between 
the  hay  and  the  grain  was  kept  the  same  at  all  times.  The  cows  were 
kept  in  the  barn  during  the  night  and  in  an  adjoining  lot  having  no 
grass  or  other  food  during  the  day.  The  animals  were  fed  and 
milked  twice  daily,  at  5  a.  m.  and  4  p.  m.  The  ration  served  to  keep 
the  animals  in  good  condition,  and  the  production  of  milk  was  about 
typical  of  the  breeds,  although  not  equal  to  that  produced  previously 
by  the  same  animals  when  opportunity  was  given  to  vary  the  ration 
and  adapt  it  to  the  needs  of  the  individual. 

;  METHODS  OF  CALCULATION  AND  TERMINOLOGY. 

In  preparing  the  mass  of  calculations  involved  in  this  bulletin  free 
use  was  made  of  tables  prepared  by  the  several  authors  of  the  for- 
mulas. In  calculating  and  averaging  percentages  the  rule  followed 
was  to  discard  the  third  decimal  figure  when  it  was  less  than  5,  and 
to  increase  the  second  by  one  when  it  was  5  or  more.  This  will 
explain  what  may  appear  to  be  discrepancies  in  some  of  the  tables. 

To  be  strictly  accurate  the  average  of  a  series  of  specific-gravity 
determinations  must  be  made  by  first  converting  the  result  for  each 
determination  into  terms  of  specific  volume.  These  figures  may  then 
be  averaged  in  the  usual  manner  and  the  resulting  average  converted 
back  into  terms  of  specific  gravity.  The  error  introduced,  however, 
by  simply  dividing  the  sum  of  the  specific  gravities  by  the  number  of 
determinations  was  so  very  small  that  the  averages  given  in  this  bulle- 
tin were  all  made  in  this  way. 

In  order  to  avoid  confusion,  the  term  plasma"  is  employed  to 
designate  whole  milk  minus  the  fat;  "plasma  solids"  to  designate  the 
solids  in  milk  minus  the  fat;  and  "  total  solids"  the  solids  including  the 
fat. 

METHOD  OF  SAMPLING. 

The  milk  was  weighed  after  milking  and  mixed  by  pouring  it  back 
and  forth  from  one  pail  into  another.  A  sample  of  about  1  quart 
was  placed  in  a  glass  jar  bearing  the  number  of  the  cow  and  the  num- 
ber of  pounds  for  that  particular  milking,  and  delivered  to  the 
laboratory.  A  certain  number  of  cubic  centimeters  per  pound  were 
then  measured  out  and  placed  in  a  covered  receptacle  to  make  up  a 
composite  sample  to  represent  a  week's  milk  from  that  particular 
cow.  Formaldehyde  was  added  in  the  proportion  of  1  part  to  5,000 
to  preserve  the  sample.  At  the  end  of  the  week  the  composite  sample 
was  thoroughly  mixed  and  a  subsample  taken  for  chemical  analysis. 


GRAVIMETRICALLY  DETEBMINED  RESULTS. 


9 


METHOD  OF  DETERMINING  SPECIFIC  GRAVITY  AND  TOTAL  SOLIDS. 

The  specific  gravity  of  the  milk  was  determined  at  15°  C.  by  means 
of  a  Westphal  balance. 

The  determinations  of  fat  and  total  solids  were  made  by  the  Bab- 
cock  asbestos  method.  A  woolly  asbestos  was  used  in  perforated 
copper  cylinders,  and  the  determinations  were  conducted  according 
to  the  official  method  as  described  in  Bulletin  107  (revised)  of  the 
Bureau  of  Chemistry,  United  States  Department  of  Agriculture. 

COMPARISON  OF  THE  FORMULAS  WITH  GRAVIMETRIC  ALLY 
DETERMINED  RESULTS.^ 

The  main  table  showing  the  comparisons  of  the  three  formulas  in  the 
individual  cases  is  found  in  the  appendix.  Tables  1,  2,  and  3,  imme- 
diately following,  are  made  up  of  averages  from  figures  in  the  main 
table.  No  explanation  will  be  needed  to  show  how  the  various 
figures  are  obtained.  A  study  of  the  tables  will  show  that  in  the  case 
of  every  cow,  regardless  of  breed  or  individuality,  the  Babcock  for- 
mula yielded  results  closest  to  those  obtained  by  gravimetric  deter- 
mination of  the  total  solids.  A  comparison  of  the  results  obtained  by 
the  Babcock  formula  with  the  gravimetric  results  shows  that  256,  or 
59.53  per  cent,  of  the  430  cases  agree  within  0.25  per  cent,  and  that 
389,  or  90.46  per  cent,  agree  within  0.5  per  cent.  Using  Richmond's 
formula  in  the  same  way,  360,  or  83.7  per  cent,  of  the  cases  fall  within 
the  prescribed  limit  of  0.5  per  cent.  Likewise  Fleischmann's  formula 
shows  309  cases  of  agreement,  or  71.85  per  cent.  With  the  Hehner 
and  Richmond  formula,  the  figures  of  which  are  omitted  from  this 
publication  for  reasons  previously  stated,  there  was  a  similar  agree- 
ment in  387,  or  89.99  per  cent,  of  the  cases,  showing  that  this  formula 
yields  results  practically  identical  with  those  derived  from  the  Bab- 
cock formula. 

A  study  of  Table  4  will  reveal  the  fact  that  the  calculated  figures 
from  the  Babcock  formula  do  not  differ  from  the  gravimetric  figures 
in  any  uniform  direction,  but  that  the  plus  and  minus  differences 
nearly  counterbalance.  That  they  do  nearly  counterbalance  is  shown 
conclusively  in  Table  3,  where  it  will  be  seen  that  the  average  figure 
for  the  calculated  solids  for  the  entire  series  of  comparisons  differs 
only  0.07  per  cent  from  the  corresponding  average  figure  determined 
gr  avime  trically . 

1  In  some  cases  in  this  bulletin  the  specific  gravities  are  given  in  terms  of  Quevenne  degrees.  These 
degrees,  of  course,  refer  to  the  arrar^gement  of  the  scale  on  the  style  of  the  lactometer  known  as  the  Quevenne 
lactometer.  Quevenne  degrees  are  converted  into  specific  gravity  by  dividing  by  1,000  and  then  adding 
1  to  the  quotient.   For  example,  if  the  Quevenne  reading  is  32.5  the  specific  gravity  is  1.0325. 

76857°— Bull.  134—11  2 


10 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


Table  1. — Number  of  instances  where  Jhe  total  solids  calculated  by  the  Babcock,  Richmond, 
and  Fleischmann  formulas  lie  within  stated  limits  of  the  gravimetrically  determined  total 
solids. 

[Number  of  cases.] 


Cow  No. 

Between 
0  and  0.24 
per  cent. 

Between 
0.25  and  0.49 
per  cent. 

Between 
0.50  and  0.74 
per  cent. 

Between 
0.75  and  1 
per  cent. 

Over  1  per 
cent. 

Babcock. 

Richmond. 

Fleischmann. 

Babcock. 

Richmond. 

Fleischmann. 

Babcock. 

Richmond. 

Fleischmann.  I 

Babcock. 

Richmond. 

Fleischmann. 

Babcock. 

Richmond. 

Fleischmann. 

4  

20 
15 
15 

15 
14 
18 

10 
10 
14 

4 
16 
16 

6 
9 
11 

9 
7 
11 

1 
6 
2 

4 
12 
4 

4 
11 
8 

2 
9 

99  

2 

Total  for  breed  

50 

30 
20 
30 

47 

26 
17 
26 

34 

16 
16 
23 

36 

12 
15 
6 

26  1  27 

9 

3 
5 
9 

20 

6 
7 
6 

23 

10 
7 
2 

1 

"i" 

2 

1 
1 
3 

11 

2 
5 
7 

205  

206  

13 
15 
10 

17 
12 
13 

1 

1 

2 

209  

Total  for  breed  

300  

1 

1 

80 

69 

55 

33 

38 

42 

17 

19 

19 

2 

5 

14 

1 

2 

3 

12 
14 
17 
23 
9 

15 
14 
14 
22 
8 

15 
8 
11 
16 
4 

11 
9 
5 

12 
2 

9 
7 
9 
11 
2 

5 
9 
8 
12 
6 

3 
1 
3 
1 
1 

1 
3 
2 
3 
1 

5 
6 
4 
7 
1 

1 

1 
1 
2 
1 
1 

301  

301  

302  

1 

.... 

1 

Total  for  breed  

400  

75 

73 

54 

39 

38 

40 

9 

10 

23 

1 

2 

6 

1 

1 

23 
21 
7 

21 
17 
3 

14 
11 
3 

11 
7 
7 

10 
10 
8 

14 
10 
5 

1 
1 

3 
2 
3 

5 
7 
6 

1 

2 
1 

402  

403  

Total  for  breed  

51 

41 

28 

25 

28 

29 

2 

8 

18 

1 

3 

Total  cases  

256 

230 

171 

133 

130 

138 

37 

57  83 

3 

10 

34 

1 

3 

4 

Table  2. — Data  of  Table  1  expressed  in  percentages. 
[Per  cent  of  cases.] 


Cow  No. 

Between  0  and 
0.24  per  cent. 

Between  0.25 
and  0.49  per 
cent. 

Between  0.50 
and  0.74  per 
cent. 

Between  0.75 
and  1.00  per 
cent. 

Over  1  per 
cent. 

M 
o 

8 
m 

fl 

O 

1 

d 

1 

o 
'53 

o 
,o 
& 
pq 

1 

d 

g 
1 

o 

yi 

'53 

8 

% 
pq 

g 

1 
5 

d 
d 

1 

o 

in 

'S 

o 
« 

M 

13 
Cl 
o 

1 

d 

9 
1 

o 
8 

24. 32 

M 
o 
o 
o 

«  ■ 

g 

s 

o 

s 

d 
1 

S 

4  

80 

40.54 
45.  45 

60 

37.84 
54. 55 

40 

27.03 
42.42 

16 

43.24 
48.49 

24 

24.32 
33.34 

36 

18.92 
33.34 

4 

16.22 
6.06 

16 

32.43 
12.12 

16 

29. 73 
24. 24 

99  

5.41 

118  

Percent  for  breed. 
205  

52. 64 

49.48 

35.80 

37. 89 

27.. 37 

28.41 

9.47 

21.05 

24.21 

2.10 

U..58 

1 

63. 83 
50 

65.21 

55.33 
42.50 
56.52 

34.04 

40 

50 

2^.M  27.66 

36.16,  6.38 
30  12.50 
28.2619.56 

12.76 
17.50 
13.05 

21.27 
17.50 
4.35 

2. 13 
2.' 17 

2.13 
2.50 
6.52 

4.26 
12. 50 
15.22 

2. 13 

2.13 

4.26 

206  

37. 50 
13.04 

37.50 
21.74 

209  

2.17 

2.17 

Percent  for  breed. 

300  

300  

60. 15 

51.87 

41.35 

24.80 

28.57 

31.51 12.77 

19.2311.53 
37.501  4.17 

14.29 

14.29 

1.50 

3.67 

10.52 

.75 

1.50 

2.26 

46. 15 
58.33 
68 

62. 16 

57.69 
58.34 
56 

59.46 
m  fis 

57. 69 
33.33 
44 

43.24 
33.34 

42.32 
37.50 
20 

32.44 
16.66 

34.61 
29.17 
36 

3. 85 
12.50 
8 

8.11 
8.33 

19.23 

25 
16 

18.92 
8.33 

3.85 

3.85 
4.17 

8 

2. 70 
8.33 

4.84 

301  

32 

12 

2.70 
8.34 

301  

302  

29.73:32.44 
16.66.50 

2.70 

"8."33 

2.70 

2.70 

Per  cent  for  breed. 
400  

60.49 

65.  70 
72.41 
50 

59.68 

43. 55 

31.46 

30.65 

32. 26 

7.26 

8.07 

18.'55 

.81 

.81 

.81 

.81 

60 

.58.02 
21.43 

40 

.37. 93 
21.43 

31.44 
24.14 
50 

28.  57 
34.48 
57.14 

40 

34.48 
35.  72 

2.86 
3.45 

8.  57 
6. 90 

21 . 43 

14.29 
24.14 
42.85 

2.86 

^771 
3.45 

402  

403  

Percent  for  breed. 
Total  percent  

65.39 

51.29 

34. 61 

32.05 

37.18 

37. 18 
32.09 

2.56 

10.26 

24.36 

1.28 

3.85  

59.53 

53.48 

39.76 

30.93 

30.23 

8.60 

13.25 

19.30 

.70 

2.32 

7.90|  .23 

.70 

.93 

SPECIFIC  GRAVITY  OF  MILK  SOLIDS. 


11 


Table  3. — Average  specific  gravity,  nitrogen,  sugar,  fat,  and  total  solids  for  each  cow, 
each  breed,  and  the  total  average. 


Cow  No. 

Specific 
gravity 
of  milk. 

Total 
nitro- 
gen. 

Sugar. 

IT  of 

Solids 
not  fat. 

Total 
solids- 
gravi- 
metric. 

Total 
solids— 
Bab- 
cock. 

Total 
solids- 
Rich- 
mond. 

Total 
solids— 
Fleisch- 
mann. 

4  

99  

118  

Average  for  breed  

205  

206  

209  

Average  for  breed  

300  

300  

301  

301  

302  

Average  for  breed  

400  

402  

403  

Average  for  breed  

Total  average  

Degrees. 
33. 4 
32.9 
34.2 

P.  ct. 
0.61 
.53 
.65 

P.  ct. 
4.  79 
4. 99 
4. 87 

P.  Ct. 
4.88 
4.70 
5.39 

P.  ct. 

9. 23 
8.95 
9. 66 

P.  ct. 
14. 19 
13.65 
15.05 

P.  ct. 
14.21 
13.87 
15.02 

P.  ct. 
14.35 
14.02 
15.16 

P.  ct. 
14.47 
14. 13 
15.28 

33.5 

:60 

4.88 

4.99 

9.  28 

14.30  1  14.37 

14.51 

14.63 

32.9 
29.8 
31.4 

.47 
.44 

.52 

5.09 
4. 25 
4.  29 

3.23 
2.96 
3.09 

8.  78 
7.98 
8.45 

11.99  i  12.10 
10.94  11 
11.51  1  11.54 

12. 24 
11.16 
11.70 

12.  .37 
11.26 
11.80 

31.4 

.48 

4.  54 

3.09 

8.  40 

11.48  11.55 

11.70 

11.81 

3.3.3 
31.8 
.33. 1 
32.6 
31.7 

.60 
.48 
.54 
.51 
.55 

4. 86 
4. 84 
5.02 

5 

4. 78 

4. 20 
3.49 
4. 28 
3.84 
4.49 

9.23 
8.  56 
9.11 
8.  85 
8. 77 

13.43 
12.05 
13.39 
12.72 
13. 24 

13.38 
12. 12 
13.41 
12.77 
13.32 

13.52 
12.28 
13. 54 
12.93 
13.48 

13. 64 
12.  .39 
13. 67 
13.04 
13. 58 

32.5 

.54 

4.  90 

4. 06 

8.  90 

12.96  !  13 

13. 15 

13.26 

33.9 
33.8 
33.2 

.53 
.54 
.49 

5.09 
4. 97 
5.23 

3.86 
4.04 
3.34 

9. 22 
9. 16 
8. 79 

13.08 
13.20 
12. 12 

13. 12 
13.28 
12.31 

13.24 
13.41 
12.  49 

13.38 
13.55 
12. 50 

33.6 

.52 

5. 10 

3.75 

9.06 

12.80  1  12.90 

13.05 

13.14 

32.8 

.54 

4.86 

3. 97 

8.91 

12.89  12.96 

13.10 

13.21 

THE  SPECIFIC  GRAVITY  OF  MILK  SOLIDS. 

Assuming  that  milk  is  a  mixture  of  milk  plasma  and  fat,  it  will  be 
seen  at  once  that  if  the  specific  gravities  of  the  fat  and  of  the  plasma 
solids  were  constant  quantities  the  relation  of  the  specific  gravity  of 
the  milk,  the  percentage  of  fat,  and  the  percentage  of  plasma  solids 
could  be  expressed  mathematically.  From  such  a  mathematical 
relation  it  would  be  but  a  step  to  derive  a  formula  for  finding  any  one 
of  these  factors  when  the  other  two  were  given. 

The  specific  gravity  of  butter  fat  is  about  0.93  at  15°  C,  the  varia- 
tion from  this  figure  in  different  samples  being  so  slight  as  to  be 
negligible  for  all  practical  purposes.  It  may  then  be  considered  as  a 
constant,  and  is  so  treated  in  the  formulas  compared  in  the  previous 
part  of  this  bulletin. 

The  specific  gravity  of  the  plasma  solids  is  not  a  constant,  but 
varies  in  different  samples  of  milk.  This  variation  is,  however,  not 
a  large  one,  being  generally  within  comparatively  narrow  limits  in 
normal  milk.  It  is  because  of  these  narrow  limits  that  formulas  are 
admissible. 

Richmond,^  working  in  England,  found  from  the  analyses  of  over 
200  samples  of  milk  the  average  specific  gravity  of  the  plasma  solids 
to  be  1.616.  Fleischmann  ^  obtained  the  figure  1.6007  from  the  aver- 
age of  a  large  number  of  samples  from  cows  in  North  Germany.  The 


1  Richmond's  Dairy  Chemistry,  p.  6.   London,  1899. 

2  Fleischmann's  Book  of  the  Dairy,  p.  33.   London,  1896. 


12 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


latter  investigator  has  published  a  formula  for  calculating  the  specific 
gravity  of  the  plasma  solids  when  the  specific  gravity  of  the  milk,  the 
percentage  of  fat,  and  the  percentage  of  total  solids  are  known,  thus: 

 sXo(t-f)  

^~100Xo-sXo(100-0-s/ 

The  values  for  the  specific  gravity  of  plasma  solids,  the  specific 
gravity  of  milk,  the  percentage  of  total  solids,  the  percentage  of  fat, 
and  the  specific  gravity  of  the  fat  in  this  formula  are  denoted, 
respectively,  b}''  the  letters  n,  s,  t,f,  and  o. 

Applying  this  formula  to  the  average  of  the  430  determinations 
given  in  Tables  1,  2,  and  3  it  is  found  that  1.638  is  the  average 
specific  gravity  of  the  plasma  solids. 

It  has  already  been  noted  that  the  Fleischmann  formula  gave 
figures  higher  than  the  Richmond,  which  in  turn  gave  figures  higher 
than  the  Babcock.  Since  the  average  of  the  total  solids  determined 
by  the  latter  agreed  very  closely  with  our  gravimetrically  determined 
total  solids,  it  may  be  inferred  that  if  Babcock  had  given  a  figure  for 
the  specific  gravity  of  plasma  solids  to  correspond  with  his  revised 
formula,  it  would  have  been  very  close  to  our  figure.  It  may  be 
seen  that  the  difference  between  these  three  formulas  is  largely  due 
to  the  difference  in  the  specific  gravity  of  the  plasma  solids  of  the 
milk  chosen  by  the  respective  investigators  to  represent  the  normal. 

As  previously  noted,  Babcock's  original  formula  appeared  in  1891 
and  its  corrected  form  in  1895.    As  it  originally  stood  it  was: 

Plasma  -lid.  =  (j^^|4^-  l)x  (100-/)  2.6 

In  the  above,  S  represents  the  specific  gravity  and/  the  percentage 
of  fat.  Subsequent  to  its  publication  Babcock  found  the  constant, 
2.6,  too  high  and  changed  it  to  2.5,  so  that  the  formula  as  it  now 
stands  is: 

Plasma  solids  =  (^„,^^"^^-g^^-  l)x  (100 -/) 2.5 

This  revised  form  is  the  one  used  in  the  former  part  of  this  bulletin.* 
In  deriving  this  formula  Babcock  assumes  that  the  difference 
between  the  specific  gravity  of  water  and  that  of  milk  plasma  is 
nearly  in  direct  proportion  to  the  solids  which  the  plasma  contains,^ 
and  that  if  this  difference  be  divided  by  a  constant  factor  which 

1  With  the  exception  of  the  introduction  of  a  few  intermediate  steps  and  the  substitution  of  the  term 
plasma  for  serum,  the  subject-matter  showing  the  derivation  of  the  Babcoclc  formula  was  taken  almost 
verbatim  from  his  original  article,  to  which  reference  has  already  been  made.  When  the  revised  formula 
was  published  no  figures  for  the  values  of  x  and  a  were  given.  Rather  than  use  his  original  figures,  which 
are  now  obsolete,  it  was  thought  advisable  to  use  our  own  figures  for  the  purposes  of  illustration;  hence 
the  factor  2.47  will  be  found  in  the  resulting  formula  instead  of  2.5. 

''  Dr.  Babcock  calls  attention  to  the  fact  that  this  assumption  is  not  quite  correct  (see  Twelfth  Annual 
Report,  Wisconsin  Agricultural  Experiment  Station,  p.  121),  since  if  the  plasma  solids  were  always  of  the 
same  composition  the  specific  gravity  of  the  plasma  solids  and  the  plasma  would  change  at  different  rates. 
This  error,  he  states,  is  a  very  small  one  and  is  counterbalanced  by  the  variation  in  the  composition  of  the 
plasma  solids  in  normal  milk. 


SPECIFIC  GRAVITY  OP  MILK  SOLIDS. 


13 


represents  the  increase  in  specific  gravity  caused  by  1  per  cent  of 
plasma  solids  the  result  will  be  the  percentage  of  solids  in  the  plasma. 
If  the  percentage  of  solids  in  the  plasma  found  in  this  way  be  multi- 
plied by  the  percentage  of  plasma  in  the  milk  and  the  product  divided 
by  100,  the  result  will  be  the  percentage  of  plasma  solids  in  the  milk 
Let 

/=  percentage  of  fat  in  any  milk. 
100 —/=  percentage  of  plasma  in  any  milk. 
;S'  =  specific  gravity  of  milk  at  60°  F. 
0.93  =  specific  gravity  of  butterfat  at  60°  F. 
0?  =  specific  gravity  of  plasma  at  60°  F. 
a  =  increase  in  the  specific  gravity  of  the  plasma  caused 
by  1  per  cent  of  plasma  solids. 

Then,  I.— 

Percentage  of  plasma  solids  in  any  milk  =  X 
=  volume  in  c.  c.  of  100  grams  of  milk. 

"^^^  ^=  volume  in  c.  c.  of  plasma  in  100  grams  milk. 
f 

or  1.0753/=  volume  in  c.  c.  of  fat  in  100  grams  milk. 

Since  the  volume  of  the  milk  equals  the  sum  of  the  volumes  of  fat 
and  plasma,  then 

o  X 

Clearing  of  fractions  and  reducing 

100a;  =  lOOS  -  Sf+ 1.07  bSSfx 
Transposing  and  combining 

x(100  -  1.0753;S/)  =  lOOSf-Sf 
^  lOOS-Sf 
^^^^100-1.0753>S/ 
II.  By  first  getting  a  value  for  x  from  a  large  number  of  analyses  a 
is  found.    Subtract  1  from  x  and  divide  the  remainder  by  the  per- 
centage of  solids  which  the  plasma  contains.    The  percentage  of 
solids  in  the  plasma  is  found  by  dividing  the  percentage  of  plasma 
solids  in  the  milk  by  the  percentage  of  plasma  (100—/)  and  multi- 
plying by  100. 

The  value  of  a  in  our  work  is  0.004044. 
Substituting  the  value  of  x  and  a  in  I. 

lOOS-Sf 
100-1.0753/S/  100-/ 
.004044         ^  100 


then 

ClOQ^f  0753^/~  0^  ^100  ~/)  X  2.4703  =  percentage  of  plasma 

solids  in  the  milk. 


14  ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 

The  percentage  of  total  solids  is  found  by  adding  the  percentage  of 
fat  to  the  percentage  of  plasma  solids. 

It  will  readily  be  seen  that  Babcock's  value  of  representing  the 
increase  in  specific  gravity  of  the  plasma  caused  by  1  per  cent  of  the 
plasma  solids  depends  directly  upon  the  specific  gravity  of  the  plasma 
solids.  This  is  a  common  point  of  weakness  in  all  formulas  derived 
for  the  same  purpose. 

Since  the  plasma  solids  are  composed  of  several  solids,  chief  of 
which  are  milk  sugar,  proteins,  and  ash,  the  specific  gravity  of  the 
plasma  solids  must  depend  upon  the  specific  gravity  of  the  various 
components  taken  individually.  Richmond  ^  states  that  the  specific 
gravity  of  milk  sugar  is  1.666,  that  of  the  proteins  1.346,  and  that  of 
the  ash  4.12.  A  change  in  the  ratio  of  the  milk  sugar  and  the  pro- 
teins will  affect  the  specific  gravity  of  the  plasma  solids  and  conse- 
quently the  value  of  a.  With  a  milk  containing  an  abnormally  high 
percentage  of  sugar  the  total  solids  calculated  by  the  formulas  would 
be  theoretically  too  high.  They  would  be  too  low  under  the  reverse 
condition. 

This  is  very  well  shown  in  the  table  below,  the  results  in  which  are 
obtained  from  milk  of  a  cow  of  the  Shorthorn  breed  at  the  parturition 
period.  As  is  well  known,  the  milk  taken  at  this  time  is  abnormally 
high  in  proteins,  while  the  milk  sugar  is  abnormally  low.  The  cow 
freshened  on  the  morning  of  October  23. 


Table  4. — Showing  application  of  the  Bahcock  formula  to  colostrum  milk. 


Date. 

Total 
nitrogen. 

Fat. 

Sugar. 

Total 

Gravi- 
metric. 

solids. 

Babcock 
formula. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Oct.  23— a.  m  

2. 26 

1.30 

2.65 

22.22 

12. 86 

Oct.  24— a.  m  

1.24 

3.26 

3.81 

15.78 

12.55 

Oct.  24— p.  m  

1.09 

4.57 

4. 41 

10.  53 

14.06 

Oct.  25— a.  m  

.98 

5. 42 

4. 89 

17. 19 

15.  04 

Oct.  25— p.  m  

.93 

5.08 

4.63 

16.34 

14.67 

Oct.  26— a.  m  

.87 

6. 23 

4.79 

17.04 

16. 01 

Oct.  26— p.  m  

.82 

5.35 

5.40 

16. 06 

14.88 

Oct.  27— a.  m  

.79 

5.87 

5.  53 

16.  85 

15.53 

Oct.  27— p.  m  

.73 

5.60 

4.  96 

15. 26 

15.18 

Table  5  was  prepared  from  averages  given  in  Table  3.  The  specific 
gravity  of  the  plasma  and  the  increase  in  specific  gravity  of  the 
plasma  caused  by  1  per  cent  of  plasma  solids  (Babcock's  value  a) 
were  calculated  by  means  of  the  Babcock  formula.  The  specific 
gravity  of  the  plasma  solids  was  calculated  by  the  formula  of  Fleisch- 
mann,  to  which  reference  has  already  been  made.  The  last  column 
of  figures  shows  the  factor  which  would  result  in  each  case  were  our 
figures  for  the  value  of  a  substituted  for  Babcock's  in  his  formula. 


>  Richmond's  Dairy  Chemistry,  p.  65. 


ACCURACY  OF  LACTOMETERS.  15 


Table  5. — Average  data  for  each  breed  of  cows. 


Breed. 

Num- 
ber of 
anal- 
yses. 

Average 
specific 
gravity 
of  milk. 

Average 

fat 
content. 

Average 
total 
solids. 

Average 
specific 
gravity 
of  plasma. 

Average 
specific 
gravity 
of  plasma 
solids. 

Average 
value 
for  a. 

Factor. 

Jersey  

Holstein  

Ayrshire  

Shorthorn  

All  breeds  

95 
133 
124 

78 
430 

1.0335 
1.0314 
1.0325 
1.0336 
1.0328 

Per  cent. 
4. 99 
3.09 
4.06 
3.  75 
3.97 

Per  cent. 
14.30 
11.48 
12.97 
12.  80 
12. 89 

1.03958 
1.03500 
1.03734 
1.03811 
1.03752 

1.648 
1.624 
1.637 
1.650 
1.638 

0. 004052 
.  004038 
.004025 
.  004049 
.  004044 

2. 468 
2. 477 
2.485 
2.469 
2.470 

It  will  be  noted  that  there  is  no  great  variation  in  the  figures  in 
the  last  three  columns,  and  also  that  the  factor  is  but  slightly  different 
from  Babcock's  2.5.  This  would,  of  course,  follow  from  the  close 
agreement  between  the  grand  average  figures  for  the  gravimetric 
total  solids  and  that  calculated  by  the  Babcock  formula. 


EXPERIMENTS   TO   DETERMINE   ACCURACY   OF  LACTOMETERS. 

Having  found  which  formula  was  best  adapted  for  the  purpose, 
the  next  question  which  naturally  suggests  itself  is  w^hether  the  ordi- 
nary lactometer  when  used  to  determine  the  specific  gravity  of  milk 
is  sufficiently  accurate. 

Thirteen  lactometers  were  available  for  comparison;  11  of  these 
were  Quevenne  lactometers  and  2  were  of  the  type  known  as  the  New 
York  Board  of  Health  lactometer.  These  were  thought  to  represent 
fairly  well  the  ordinary  lactometers  on  the  market.  They  were  com- 
pared with  the  Westphal  balance  on  three  different  samples  of  milk, 
with  the  following  results: 


Table  6. — Showing  comparisons  of  various  lactometers  with  Westphal  balance. 


Instniment. 

Specific  gravity  of  milk 
samples. 

Instrument. 

Specific  gravity  of  milk 
samples. 

Skim 
milk. 

Hol- 
stein. 

Hol- 
stein 
fresh. 

Skim 
milk. 

Hol- 
stein. 

Hol- 
stein 
fresh. 

Quevenne  lactometer  1 . . . 

1.0345 

1.0315 

1.0325 

Quevenne  lactometer  9. . . 

1.0350 

1.0320 

1.0330 

Quevenne  lactometer  2. . . 

1.0340 

1.0310 

1.0320 

Quevenne  lactometer  10. . 

1.0335 

1.0310 

1.0318 

Quevenne  lactometer  3. . . 

1.0340 

1.0315 

1.0325 

Quevenne  lactometer  11. . 

1.0350 

1.0320 

1.0330 

Quevenne  lactometer  4. . . 

1.0335 

1.0300 

1.0320 

New    York    Board  of 

Quevenne  lactometer  5. . . 

1.0330 

1.0300 

1.0315 

Health  lactometer  1  

1.0328 

1.0307 

1.0319 

Quevenne  lactometer  6 . . . 

1.0340 

1.0310 

1.0325 

New    York    Board  of 

Quevenne  lactometer  7... 

1.0360 

1.0330 

1.0340 

Health  lactometer  2  

1.0299 

1.0281 

1.0290 

Quevenne  lactometer  8 . . . 

1.0370 

1.0335 

1.0350 

Westphal  balance  

1. 0345 

1.0313 

1.0325 

A  glance  at  the  foregoing  figures  will  show  discrepancies  which 
are  sufficient  in  some  cases  to  account  for  as  much  as  1  per  cent  of 
total  solids  calculated  from  the  Babcock  formula.  Of  course,  much 
of  the  discrepancy  is  due  to  the  fault  of  the  manufacturer  in  not 


16 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


properly  calibrating  the  instruments.  However,  in  none  of  the 
lactometers  tested  was  the  scale  divided  into  less  than  whole  Quevenne 
degrees.  Fractions  of  degrees  could  be  read  only  by  interpolation, 
and  then  the  divisions  were  generally  so  narrow  that  a  closer  inter- 
polation than  one-half  of  a  degree  was  impossible;  in  fact,  in  some 
cases  it  was  hardly  possible  to  read  closer  than 
whole  degrees.  One  Quevenne  degree  with  a  Bab- 
cock  formula  will  account  for  0.25  per  cent  of  total 
solids.  It  is  therefore  obvious  that  the  ordinary 
lactometer  is  unsuited  for  other  than  very  gross 
results. 

The  sensitiveness  of  the  hydrometer,  or  lactom- 
eter, as  it  is  termed  when  made  for  the  special  pur- 
pose of  determining  the  specific  gravity  of  milk, 
depends  upon  the  ratio  of  the  size  of  the  bulb  to  the 
diameter  of  the  stem.  The  larger  the  bulb  is  in  pro- 
portion to  the  diameter  of  the  stem,  the  more  sensi- 
tive will  be  the  lactometer,  or,  in  other  words,  the 
longer  will  be  the  spaces  representing  units  on  the 
scale.  A  lactometer,  then,  may  be  made  more  sen- 
sitive by  either  diminishing  the  size  of  the  stem  or 
by  enlarging  the  bulb.  But  the  smaller  the  stem 
the  more  fragile  is  the  instrument,  and  the  larger 
the  bulb,  the  more  cumbersome. 

In  designing  a  lactometer  for  our  work  several 
points  were  taken  into  account:  (1)  That  it  should 
accommodate  the  usual  ranges  of  normal  milk; 
(2)  that  it  should  have  scale  divisions  representing 
tenths  of  Quevenne  degrees;  and  (3)  that  it  must 
be  neither  too  fragile  nor  too  cumbersome  for  prac- 
tical use  outside  of  a  chemical  laboratory. 

After  considerable  experimenting  in  the  labora- 
tory the  dimensions  of  an  instrument  were  decided 
upon  and  several  were  made  to  order  from  our 
specifications.    (See  fig.  1.) 

In  order  to  test  these  lactometers  against  the 
Westphal  balance,  salt  solutions  were  used,  and  the 
following  results  were  obtained : 


Fig.  1.— Lactometer 
designed  for  use  in 
experimental  work. 


Table  7. — Comparison  of  new  lactometers  with  Westphal  balance,  using  salt  solutions. 


Solution. 

West- 
phal. 

Lactom- 
eter I. 

Lactom- 
eter 11. 

1.0245 
1.0283 
1.0315 
1.0352 

1.0248 
1.0287 
1.0318 
1.0351 

1.0248 
1.0287 
1.0319 
1.0352 

TESTS  OF  BABCOCK  FORMULA  AND  NEW  LACTOMETER.  17 

Little  comment  is  required  on  the  above  figures,  as  it  is  seen  that 
the  results  obtained  with  the  lactometers  are  practically  identical 
with  those  of  the  Westphal  balance. 

TESTS   OF  BABCOCK  FORMULA   AND  NEW  LACTOMETER  WITH 
INDIVIDUAL  MILKINGS. 

Since  the  figures  given  in  the  first  part  of  this  bulletin  were  all 
based  on  results  obtained  on  composite  samples  from  individual  cows, 
it  was  deemed  desirable  at  this  point  to  test  the  Babcock  formula 
on  milk  from  individual  milkings  and  at  the  same  time  to  compare 
the  figures  obtained  by  the  new  lactometers  and  the  Westphal  bal- 
ance on  the  same  milk.  The  only  change  in  the  laboratory  procedure 
was  that  the  percentage  of  fat  was  obtained  by  the  Babcock  test 
instead  of  by  the  extraction  method. 

Four  cows  were  selected  with  which  to  make  the  tests  under  con- 
ditions comparable  with  those  found  in  making  official  tests  of  dairy 
cattle.  For  this  purpose  pure-bred  cows  were  used,  representing  four 
breeds.  These  cows  were  milked  and  fed  three  times  daily — at 
5  a.  m.,  1  p.  m.,  and  8  p.  m.  The  animals  remained  in  the  barn  the 
greater  part  of  the  time.  They  were  allowed  the  freedom  of  a  lot 
from  two  to  four  hours  in  the  forenoon  and  from  one  to  two  hours 
in  the  afternoon.  Each  animal  was  fed  according  to  her  individual 
capacity  and  characteristics.  The  cows  were  on  ofiicial  test  at  the 
time  these  samples  were  secured  and  were  receiving  such  treatment 
as,  in  the  judgment  of  the  herdsman,  would  give  the  best  results 
for  this  purpose.  The  rations  consisted  of  corn,  silage,  alfalfa  hay, 
corn  meal,  bran,  oats,  and  oil  meal  in  somewhat  varying  proportions. 
Table  8  gives  more  specific  data  regarding  the  four  cows  used.  The 
duration  of  the  test  was  seven  days,  the  average  yields  of  milk  and 
of  butter  fat  for  this  period  being  as  follows: 


Table  8. — Milking  records  of  cows  used  in  tests. 


No.  of 
Cow. 

Breed. 

Days 

in 
milk. 

Average 

yield  of 
milk  per 
day. 

Average 
yield  of 
fat  per 
day. 

16    ..  . 

Jersey  

367 
119 
20 
258 

Pounds. 
10.9 
16.7 
13.7 
10.5 

Pounds. 
0.57 
.57 
.53 
.43 

204 

Holstein  

300, 

Ayrshire  

401.  .  , 

Snorthorn..:  

18 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


The  results  of  the  work  on  the  individual  milkings  from  the  cows 
described  in  the  above  table  are  found  in  Tables  9,  10,  11,  and  12, 
next  following. 


Table  9. — Lactometer  results  on  individual  milkings  from  Holstein-Friesian  cow  No.  204. 


Sample  No. 

Specific  gravity— 

Fat. 

Percentage  of  total  solids— 

Westphal 
balance. 

i^actom- 
eter  I. 

Lactom- 
eter II. 

Gravi- 

W^est- 
phal. 

i-^actom- 
eter  I. 

Liactom- 
eter  II 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

T  1 

1 

0310 

1.0321 

1 

0320 

2 

9 

11.59 

11.23 

11.52 

11.49 

L9 

1 

0320 

1.0326 

1 

0324 

3 

2 

12.26 

11.85 

12 

11.95 

L3 

1 

0315 

1. 0315 

1 

0312 

4 

3 

12. 93 

13. 05 

13. 05 

12  97 

L4 

1 

0308 

L0312 

1 

0310 

3 

5 

1L91 

11^91 

12!  01 

1L96 

L5  

1 

0317 

1.0.319 

1 

0317 

2 

9 

11.57 

11.41 

11.46 

11.41 

L6  

1 

0316 

1.0320 

1 

0318 

3 

8 

12. 72 

12  Al 

12. 57 

12.  52 

L7  

1 

0336 

1.0335 

1 

0336 

3 

4 

12.  70 

12. 49 

12. 47 

12.  49 

L8  

1 

0321 

1.0323 

1 

0324 

3 

3 

12. 23 

12 

12.05 

12.07 

L9  

1 

0299 

1.0300 

1 

0301 

3 

5 

12.  32 

11.69 

11.71 

11.74 

LIO  

1 

0320 

1.0325 

1 

0322 

3 

5 

12.26 

12. 21 

12. 34 

12.26 

Lll  

1 

0341 

1.0337 

1 

0335 

2 

93 

11.95 

12.08 

11.98 

11.93 

L12  

1 

0318 

1. 0316 

1 

0314 

4 

12.62 

12. 76 

12.71 

12.  66 

L13  

1 

0318 

1.0320 

1 

0320 

3 

3 

12. 07 

11.92 

11.97 

11.97 

LU  

1 

0327 

1.0322 

1 

0322 

2 

75 

11.39 

11.49 

11.36 

11.36 

L15  

1 

0303 

1.0298 

1 

0298 

4 

2 

12.84 

12.63 

12.50 

12.50 

L16  

1 

0304 

1.0312 

1 

0308 

4 

23 

13.17 

12. 71 

12.91 

12. 81 

L17  

1 

0327 

1.0324 

1 

0322 

2 

8 

11.59 

11.  55 

11.47 

11.42 

L18  

1 

0312 

1.0312 

1 

0309 

3 

95 

12.60 

12.55 

12.55 

12.48 

L19  

1 

0313 

1.0320 

1 

0317 

3 

70 

12.  61 

12.28 

12. 45 

12.  38 

L20  

1 

0313 

1.0321 

1 

0319 

3 

35 

12.07 

11.86 

12.08 

•12.01 

L21  

1 

0310 

1.0317 

1 

0317 

3 

78 

12,44 

12. 32 

12.50 

12.50 

Table  10. — Lactometer  results  on  individual  milkings  from  Jersey  cow  No.  16. 


Sample  No. 

Specific  gravity— 

Fat. 

Percentage  of  total  solids- 

West- 
phal 
balance. 

Lactom- 
eter I. 

Lactom- 
eter II. 

Gravi- 
metric. 

West- 
phal. 

Lactom- 
eter I. 

Lactom- 
eter II. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

L22  

1.0325 

1.0329 

1.0327 

5.2 

14.92 

14.39 

14.49 

14.44 

L23  

1.0346 

1.0348 

1.0348 

5.1 

14.97 

14.79 

14.84 

14.84 

L24  

1.0325 

1.0330 

1.0329 

5.6 

15.45 

14.88 

15 

14.98 

L25  

1.0342 

1.0347 

1.0347 

4.88 

14.65 

14. 45 

14. 58 

14.58 

L26  

1.0346 

1.0350 

1.0348 

4.6 

14.38 

14.19 

14.30 

14.24 

L27  

1.0333 

1.0335 

1.0333 

5.18 

14.89 

14.59 

14.64 

14.59 

L28  

1.0340 

1.0351 

1.0349 

5.25 

15.25 

14.82 

15.11 

15.05 

L29  

1.0332 

1.0338 

1.0336 

5.20 

14.56 

14.56 

14. 71 

14.66 

L30  ;  

1.0327 

1.0333 

1.0333 

5. 68 

15.33 

15.05 

15.  20 

15. 20 

L31  

1.0345 

1.0348 

1.0349 

5.40 

15. 28 

15.14 

15. 21 

15. 24 

L32  

1.0355 

1.0357 

1 . 0355 

5 

14. 85 

14.91 

14. 96 

14.91 

1.0344 

1.0348 

1.0346 

5 

14.87 

14. 62 

14.  72 

14. 67 

L34  

1.0340 

1.0342 

1.0341 

5.23 

14.86 

14.82 

14. 87 

14. 85 

L35  

1.0350 

1.0350 

1.0348 

4.93 

14.62 

14.  72 

14.  72 

14.66 

L36  

1.0330 

1.0333 

1.0330 

5.  75 

15. 50 

15.18 

15. 26 

15.18 

L37  

1.0351 

1.0354 

1.0354 

5.15 

14.93 

14.99 

15.06 

15.06 

L38  

1. 0343 

1.0347 

1.0346 

5.25 

15.09 

14.90 

15 

14.97 

L39  

1.0332 

1.0333 

1.0335 

5.55 

15.20 

14.99 

15.02 

15.07 

L40  

1. 0351 

1.0345 

1.0344 

5. 20 

15. 19 

15.05 

14.89 

14.86 

L41  

1.0354 

1.0347 

l.a346 

5.  25 

15.26 

15.18 

15 

14.97 

L42  

1.0333 

1.0333 

1.0.333 

5.30 

15. 59 

14.  71 

14. 71 

14.71 

EFFECT  OF  TEMPERATURE  ON  SPECIFIC  GRAVITY.  19 


Table  11. — Lactometer  results  on  individual  milTcings  from  Shorthorn  cow  No.  401. 


Sample  No. 

Specific  gravity— 

Fat. 

Percentage  of  total  solids — 

West- 
phal 
balance. 

Lactom- 
eter I. 

Lactom- 
eter II. 

Gravi- 
metric. 

West- 
phal. 

Lactom- 
eter I. 

Lactom- 
eter II. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

L43  

1.0340 

1. 0342 

1.0342 

3. 8 

13.44 

13.08 

13.13 

13.13 

L44  

1.0344 

1.0345 

1.0344 

3.65 

13.22 

13 

13.03 

13 

L45   

1.0340 

1.0342 

1.0342 

4. 5 

14. 43 

13.92 

13.97 

13.97 

L46  

1.0350 

1.0352 

1.0351 

3.9 

13.80 

13.45 

13.50 

13.48 

L47  

1.0352 

1.0354 

1.0353 

3 

12.  t6 

12. 41 

12. 46 

12. 44 

L48  

1.0340 

1.0343 

1.0342 

4.4 

14.29 

13.80 

13.88 

13.85 

L49  

1.0344 

1.0348 

1.0347 

4 

13.54 

13.42 

13.52 

13.50 

L50  

1.0357 

1.0363 

1.0363 

3.  7 

13.82 

13.39 

13.54 

13.54 

L51  

1.0335 

1.0337 

1.0336 

4. 8 

14.31 

14. 16 

14. 21 

14.18 

L52  

1.0308 

].0316 

1.0317 

3.  55 

11.92 

11.97 

12.17 

12. 20 

L53  

1.0355 

1 . 0360 

1 . 03G0 

2.95 

12. 67 

12. 43 

12. 55 

12. 55 

L54  

1.0344 

1.0351 

1.0349 

4.  45 

13.  .59 

13.96 

14.15 

14.09 

L55  

1.0347 

1.0348 

1.0345 

4.50 

14.14 

14. 10 

14.12 

14.05 

L56 

1.0349 

1.0352 

1.0350 

4. 45 

13.92 

14.09 

14.17 

14.12 

L57  

1.0337 

1.0339 

1.0338 

5" 

14.48 

14.46 

14.49 

14. 47 

L58  

1.0335 

1.0339 

1.0338 

4.65 

14. 23 

13.98 

14. 07 

14.05 

L59  

1 . 0350 

1.03.55 

1.0354 

3.60 

12.  73 

13.09 

13.22 

13.19 

L60  

1.0362 

1.0360 

1.0359 

4.60 

14.56 

14.60 

14. 55 

14.52 

L61  

1.0355 

1.0359 

1.0360 

4. 40 

14.37 

14.19 

14.28 

14.31 

L62  

1 . 0358 

1.0363 

1.0364 

4.15 

14.04 

13.96 

14.09 

14.11 

L63  

1.0344 

1.0351 

1.0349 

4.30 

14. 

13.78 

13.97 

13.91 

Table  12. — Lactometer  results  on  individual  millings  from  Ayrshire  cow  No.  300. 


Sample  No. 

Specific  gravity— 

Fat. 

Percentage  of  total  solids — 

West- 
phal 
balance. 

Lactom- 
eter I. 

Lactom- 
eter II. 

Gravi- 
metric. 

West- 
pbal. 

Lactom- 
eter I. 

Lactom- 
eter II. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

L64  

1.0320 

1.0327 

1.0325 

3 

11.52 

11.61 

11.79 

11.74 

L65  

1.0300 

1.0303 

1.0301 

5.10 

13.38 

13.63 

13.71 

13.66 

L66  

1.0322 

1.0323 

1.0321 

2. 50 

10.79 

11.05 

11.08 

11.03 

L67  

1.0325 

1.0327 

1.0327 

4.05 

12.99 

13 

13.06 

13.06 

L68  

1.0326 

1.0331 

1.0328 

2. 65 

11.21 

11.33 

11.47 

11.38 

L69  

1.0304 

1.0310 

1.0308 

4. 25 

12.40 

12. 71 

12.86 

12. 75 

L70  

1.0315 

1.0315 

1.0313 

2.  75 

11.01 

11.18 

11.18 

11.13 

L71  

1.0317 

1.0323 

1.0322 

3.10 

11.72 

11.66 

11.81 

11.78 

L72  

1.0313 

1.0309 

1.0305 

3.15 

11.45 

11.62 

11.61 

11.42 

L73  

1.0295 

1.0294 

1.0294 

5 

13.42 

13.39 

13.36 

13.36 

L74  

1.0.308 

1.0310 

1.0308 

3.25 

11.53 

11.61 

11.66 

11.61 

L75  

1.0320 

1.0322 

1.0319 

4. 25 

13.41 

13.12 

13.17 

13.09 

L76  

1.0315 

1.0317 

1.0316 

4.90 

13.61 

13.77 

13.82 

13.79 

L77  

1.0327 

1.0327 

1.0327 

3.80 

12.49 

12. 75 

12. 75 

12.  75 

L78  

1.0320 

1.0322 

1.0320 

4.90 

13.67 

13.90 

13.95 

13.90 

L79..  

1.0322 

1.0324 

1.0322 

4.50 

13. 54 

13.47 

13.52 

13.47 

L80  

1.0326 

1.0329 

1.0326 

3.75 

12.06 

12. 66 

12. 74 

12.66 

L81  

1.0295 

1.0290 

1.0287 

4. 75 

12.48 

13.09 

12.96 

12.89 

L82  

1.0330 

1.0328 

1.0328 

3.30 

12. 

12.22 

12.17 

12.17 

L83  

1.0296 

1.0298 

1.0297 

4.25 

12. 51 

12. 51 

12. 56 

12.54 

L84  

1.0278 

1.0280 

1.0278 

5.40 

13.15 

13.44 

13.49 

13.44 

EFFECT  OF  TEMPERATURE  ON  SPECIFIC  GRAVITY  OF  MILK. 

An  increase  in  temperature  is  accompanied  by  a  lowering  of  the 
specific  gravity  as  determined  by  the  lactometer.  To  show  the 
importance  of  maintaining  the  proper  temperature  when  using  the 
lactometer  and  at  the  same  time  to  determine  the  size  of  the  error 
introduced  by  the  difference  of  a  few  degrees  in  temperature,  specific 
gravity  determinations  were  made  at  different  temperatures  on 


20 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


several  samples  of  milk.  Only  ordinary  precautions  were  taken  in 
this  experiment,  and  the  results  are  about  such  as  would  be  obtained 
were  the  lactometers  in  practical  use. 

Samples  of  milk  were  taken  from  representatives  of  the  four  breeds 
of  cows  previously  used. 

Table  13. — Effect  of  temperature  on  specific  gravity  of  milk  when  determined  with  new 

lactometer. 


Temperatures. 

Jersey  milk. 

Shorthorn  milk. 

Ayrshire  milk. 

Holstein-Friesian 
milk. 

Specific 
gravity. 

Differ- 
ence. 

Specific 
gravity. 

Differ- 
ence. 

Specific 
gravity. 

Differ- 
ence. 

Specific 
gravity. 

Differ- 
ence. 

9°C  

1. 0364 
1. 0360 
1. 0356 
1. 0351 
1. 0345 
1. 0338 
1.  0331 

1. 0365 
1. 0361 
1.0357 
1.  0352 
1.  0347 
1.  0341 
1.  0335 

1.  0330 
1.  0327 
1.0323 
1.  0318 
1. 0313 
1.0308 
1.  0302 

1. 0291 
1. 0287 
1. 0283 
1. 0279 
1.  0275 
1. 0270 
1.0265 

11°  C  

13°  C  

15°  C  

17°  C  

19°  C  

21°  C  

Average  

0. 0004 
.0004 
.0005 
.0006 
.0007 
.0007 

0. 0004 
.0004 
.0005 
.0005 
.0006 
.0006 

0. 0003 
.0004 
.0005 
.0005 
.0005 
.0006 

0. 0004 
.0004 
.0004 
.0004 
.0005 
.0005 

.0006 

.0005 

.0005 

.0004 

Table  14. — Showing  composition  of  milk  used  in  Table  13. 


Milk. 

Fat. 

Total 
solids. 

Per  cent. 
6.2 
4 

3.7 
2.7 

Per  cent. 
15.21 
13. 78 
12. 28 
10. 02 

Shorthorn  

Holstein-Friesian  

It  will  at  once  be  seen  that  the  variation  is  different  in  different 
samples  and  also  at  different  temperatures  with  the  same  sample. 
The  greatest  variation  is  in  the  Jersey,  milk  where  the  percentage 
of  total  solids  is  highest,  and  least  in  the  Holstein-Friesian  milk, 
where  the  percentage  of  total  solids  is  lowest.  As  the  temperature 
rises  the  variation  for  each  degree  increases. 

The  average  variation  per  centigrade  degree  counting  all  four 
breeds,  is  0.00025,  which  would  account  for  an  error  of  about  0.08 
per  cent  total  solids  if  calculated  with  the  Babcock  formula.  Reduced 
to  Fahrenheit  degrees  the  error  would  be  five-ninths  of  0.08,  or  about 
0.044  per  cent  for  each  degree. 

recknagel's  phenomenon. 

Milk  when  freshly  drawn  contains  numerous  bubbles  of  gas,  and 
it  is  not  until  these  have  disappeared  that  the  specific  gravity  can 
be  determined.    It  has  been  demonstrated  by  Recknagel  ^  and  con- 


»  Milchzeitung,  Band  12,  p.  419,  Bremen,  1883. 


USE  OF  MODIFIED  LACTOMETER. 


21 


firmed  by  other  investigators  that  the  specific  gravity  of  milk  changes 
on  standing.  On  taking  the  specific  gravity  of  milk  after  the  air 
bubbles  had  escaped  and  again  several  hours  later  he  found  an 
increase.  This  peculiarity  is  called  the  Recknagel  phenomenon. 
He  ascribes  the  increase  to  a  change  in  the  volume  of  the  proteins. 
The  increase  begins  two  or  three  hours  after  milking,  and  if  the  milk 
is  held  at  about  15°  C.  continues  with  decreasing  rapidity  for  two 
days.  The  amount  of  the  increase  is  between  0.0008  and  0.0015, 
depending  on  the  richness  of  the  milk.  This  change  is  accelerated 
by  lower  temperatures,  and  the  normal  specific  gravity,  or  the  point 
where  no  further  change  takes  place,  may  be  obtained  by  keeping 
the  milk  at  5°  C.  or  lower  for  six  hours. 

HOW  TO  USE  THE  MODIFIED  LACTOMETER  AND  TABLE. 

This  section  is  designed  to  assist  those  who  may  desire  to  make 
use  of  the  modified  lactometer  described  in  the  preceding  section 
and  who  are  not  accustomed  to  using  delicate  lactometers. 

Materials  required:  1.  The  lactometer.  2.  A  pan  of  warm  water. 
3.  An  accurate  dairy  thermometer.  4.  A  suitable  cylinder  to  con- 
tain the  sample  while  making  the  reading. 

The  cylinder  may  be  made  of  tin  or  copper  and  should  have  the 
following  dimensions:  Inside  diameter,  If  inches;  height,  13  inches. 
To  prevent  it  from  tipping  over  it  should  have  a  base  of  the  same 
material  about  2f  inches  in  diameter. 

METHOD. 

Immediately  after  milking  the  milk  should  be  thoroughly  mixed 
and  a  sample  of  about  1  pint  placed  in  a  cream  bottle.  This  should 
then  be  put  into  the  refrigerator  and  kept  there  for  ten  or  twelve 
hours,  or  until  the  next  milking.  It  is  then  removed  from  the 
refrigerator  and  again  well  mixed  by  pouring  back  and  forth  several 
times  from  the  bottle  into  another  bottle  or  cup.  At  this  point  care 
must  be  taken  not  to  mix  air  with  the  milk.  This  can  be  avoided 
by  pouring  against  the  sides  of  the  receptacle  to  prevent  foaming. 
After  mixing,  the  bottle  is  placed  in  a  pan  of  warm  water  and  heated 
while  being  constantly  stirred  with  the  thermometer  until  the  tem- 
perature reaches  60°  F.  The  milk  is  then  poured  into  the  cylinder, 
which  should  also  have  been  warmed  in  the  pan  so  that  it  will  not 
cool  the  milk.  The  lactometer  is  now  quickly  lowered  into  the  milk, 
of  which  there  should  be  a  sufficient  quantity  in  the  cylinder  to  over- 
flow it,  and  allowed  to  come  to  rest.  The  point  on  the  graduated 
scale  which  is  at  the  same  level  as  the  surface  of  the  milk  is  then 
read.  This  reading  gives  Quevenne  degrees,  which  may  be  converted 
into  specific  gravity  if  desired  by  dividing  by  1,000  and  then  adding 
1  to  the  quotient. 


22 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


Owing  to  the  tendency  of  the  milk  to  form  a  meniscus  about  the 
stem  of  the  lactometer,  it  is  impossible  to  read  directly  the  exact 
point  on  the  scale  that  is  at  the  same  level  as  the  surface  of  the  milk. 
A  safe  rule  for  obtaining  a  very  close  approximation  to  the  correct 
figure  is  to  add  0.2  to  the  reading  taken  where  the  top  of  the  meniscus 
strikes  the  scale.  For  example,  if  the  scale  reads  31.8  at  the  top  of 
the  meniscus,  the  corrected  reading  in  Quevenne  degrees  would  be  32 
and  the  specific  gravity  1.032. 

Care  must  be  taken  that  the  temperature  of  the  milk  when  the  lac- 
tometer is  read  is  exactly  60°  F.;  otherwise  a  very  considerable  error 
will  be  introduced.  After  using  the  lactometer  it  should  be  rinsed  in 
clean  water,  wiped  dry,  and  restored  to  its  case. 

The  percentage  of  fat  should  be  determined  by  the  Babcock  test 
either  on  the  sample  used  for  the  specific  gravity  determination  or 
on  another  taken  at  the  same  time. 

Having  by  this  procedure  found  the  specific  gravity  of  the  milk  and 
the  percentage  of  fat,  the  total  solids  can  be  found  by  referring  to 
Table  15,  which  is  a  modified  form  of  one  published  by  Babcock.^ 
In  our  table  the  percentage  of  total  solids  is  given.  If  percentage 
of  plasma  sohds  is  wanted,  it  can  be  found  by  subtracting  the  percent- 
age of  fat  from  the  percentage  of  total  solids. 

DIRECTIONS  FOR  USING  THE  TABLE. 

If  the  specific  gravity  as  expressed  in  Quevenne  degrees  is  a  whole 
number,  the  percentage  of  total  solids  is  found  at  the  intersection  of 
the  vertical  column  headed  by  this  number  with  the  horizontal  column 
corresponding  to  the  percentage  of  fat. 

If  the  specific  gravity  as  expressed  in  Quevenne  degrees  is  a  whole 
number  and  a  decimal,  the  percentage  of  total  solids  corresponding  to 
the  whole  number  is  first  found  and  to  this  is  added  the  fraction  found 
opposite  the  tenth  under  '^Proportional  parts."  Two  examples  may 
suffice  for  illustration:  (1)  Fat,  3.8  per  cent;  specific  gravity,  32. 
Under  column  headed  32  we  find  12.57  per  cent,  corresponding  to  3.8 
per  cent  fat.  (2)  Fat,  3.8  per  cent;  specific  gravity,  32.5.  The  per- 
centage of  total  solids  corresponding  to  this  percentage  of  fat  and  a 
specific  gravity  of  32  is  12.57.  Under  ''Proportional  parts"  the  frac- 
tion 0.13  appears  opposite  0.5.  This  added  to  12.57  makes  12.70, 
which  is  the  desired  percentage. 

An  inspection  of  the  table  shows  that  the  percentage  of  total  solids 
increases  practically  at  the  rate  of  0.25  for  each  lactometer  degree 
and  1.2  for  each  per  cent  of  fat.  This  gives  rise  to  Babcock's  simpler 
formula 

Total  solids  =  i  Z+1.2/ 
(Z  =  lactometer  reading  in  Quevenne  degrees,  and /=  percentage  fat). 


I  Twelfth  Annual  Report  of  the  Wisconsin  Agricultural  Experiment  Station,  p.  124. 


USE  OF  MODIFIED  LACTOMETER  AND  TABLE. 


23 


This  simple  formula  can  be  used  in  cases  not  provided  for  in  the 
table,  and  the  error  introduced  will  be  inconsiderable. 

Table  15. —  Table  for  determining  total  solids  in  milk  from  any  given  specific  gravity 

and  percentage  of  fat. 


Per- 


Lactometer  reading  at  60"  F.  (Quevenne  degrees). 


age  of 

fat. 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

cent 

cent 

cent 

cent 

cent 

cent 

cent 

cent 

cent 

cent 

cent 

total 

total 

total 

total 

total 

total 

total 

total 

total 

total 

total 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

2.00 

8.90 

9.15 

9.40 

9. 65 

9.90 

10. 15 

10. 40 

10. 66 

10.91 

11.16 

11.41 

2. 05 

8.96 

9. 21 

9. 46 

9.71 

9. 96 

10.  21 

10. 46 

10. 72 

10. 97 

11.22 

11.47 

2. 10 

9. 02 

9. 27 

9.  52 

9.  77 

10. 02 

10  27 

10.  52 

10. 78 

11. 03 

11.  28 

11.  53 

2!  15 

9^08 

9!  33 

9. 58 

9!  83 

10!  08 

10!  33 

10.  58 

10!  84 

1L09 

11'.  34 

11^59 

2.20 

9. 14 

9. 39 

9. 64 

9.89 

10. 14 

10.  39 

10. 64 

10.90 

11.15 

11.40 

11.65 

2.  25 

9.  20 

9.45 

9.  70 

9.95 

10.  20 

10.  45 

10. 70 

10. 96 

11.21 

11.46 

11.71 

2. 30 

9.  26 

9.51 

9.76 

10. 01 

10.  26 

10.  51 

10. 76 

11.02 

11.27 

11.52 

11.77 

2.35 

9.32 

9.57 

9. 82. 

10.07 

10.  32 

10.  57 

10.  82 

11.08 

11.33 

11.  58 

11.83 

2. 40 

9.38 

9. 63 

9. 88 

10. 13 

10. 38 

10. 63 

10.  88 

11. 14 

11.39 

11.64 

11.89 

2.  45 

9.44 

9. 69 

9.94 

10. 19 

10.44 

10.69 

10.  94 

11.20 

11.45 

11.70 

11.95 



2.  50 

9. 50 

9.75 

10. 00 

10.  25 

10.  50 

10.75 

11.00 

11.26 

11.51 

11.76 

12.01 

2.  55 

9.  56 

9. 81 

10. 06 

10.31 

10.  56 

10.  81 

11.06 

11.32 

11.57 

11.82 

12.07 

2. 60 

9. 62 

9. 87 

10. 12 

10  37 

10. 62 

10  87 

11. 12 

11. 38 

11. 63 

11.  88 

12. 13 

2. 65 

9. 68 

9!  93 

10. 18 

10!  43 

10. 68 

10!  93 

11'.  18 

11!  44 

11^69 

11!  94 

12!  19 

2. 70 

9. 74 

9.99 

10.  24 

10.49 

10.  74 

10. 99 

11.24 

11.50 

11.75 

12.00 

12.  25 

2.75 

9.80 

10. 05 

10. 30 

10.  55 

10.  80 

11.05 

11.31 

11.56 

11.81 

12. 06 

12. 31 

2. 80 

9.86 

10.11 

10. 36 

10. 61 

10.  86 

11.11 

11.37 

11.62 

11.87 

12. 12 

12. 37 

2. 85 

9.92 

10. 17 

10. 42 

10.  67 

10. 92 

11.17 

11.43 

11.68 

11.93 

12. 18 

12.  43 

2. 90 

9.98 

10.  23 

10. 48 

10.  73 

10.  98 

11.23 

11.49 

11.74 

11  99 

12.  24 

12.49 

2. 95 

10.04 

10.29 

10.54 

10.  79 

11.04 

11.30 

11.55 

11.80 

12. 05 

12. 30 

12. 55 

3.00 

10.10 

10. 35 

10.60 

10. 85 

11.10 

11.36 

11.61 

11.86 

12.11 

12. 36 

12. 61 

3.05 

10. 16 

10.  41 

10. 66 

10.91 

11.17 

11  42 

11.67 

11.92 

12. 17 

12.  42 

12.68 

3. 10 

10.  22 

10. 47 

10.  72 

10. 97 

11.  23 

11.  48 

11.73 

11.98 

12.  23 

12.  48 

12.  74 

3!  15 

10!  28 

10!  53 

10!  78 

11!  03 

11!  29 

11!  54 

11!  79 

12^04 

12!  29 

12!  55 

12'.  80 

3.20 

10. 34 

10.59 

10. 84 

11.09 

11.35 

11.60 

11.85 

12. 10 

12. 35 

12.  61 

12. 86 

3.25 

10.40 

10. 65 

10. 90 

11.16 

11.41 

11.66 

11.91 

12. 16 

12.  42 

12.  67 

12. 92 

3.30 

10. 46 

10.71 

10. 96 

11.22 

11.47 

11.72 

11.97 

12.  22 

12. 48 

12.  73 

12. 98 

3.35 

10.  52 

10. 77 

11.03 

11.28 

11.53 

11.78 

12.03 

12. 28 

12.54 

12.  79 

13.04 

3.40 

10.  58 

10. 83 

11.09 

11.34 

11.  59 

11.84 

12.09 

12. 34 

12. 60 

12. 85 

13. 10 

3.45 

10. 64 

10.89 

11. 15 

11.40 

11.65 

11.90 

12. 15 

12,40 

12.  66 

12. 91 

13. 16 

3.  50 

10.  70 

10. 95 

11. 21 

11  46 

11.71 

11.96 

12.  21 



12. 46 

12.  72 

12.97 

13.22 

3.  55 

10. 76 

11.02 

11.27 

11.52 

11.77 

12. 02 

12.  27 

12.  52 

12. 78 

13.03 

13.  28 

3. 60 

10. 82 

11. 08 

11. 33 

11.  58 

11.  83 

12. 08 

12. 33 

12.  58 

12. 84 

13.09 

13. 34 

3!  65 

10!  88 

11!  14 

11!  39 

11!  64 

1L89 

12!  14 

12.  39 

12!  64 

12. 90 

13!  15 

13^40 

3.70 

10. 94 

11.20 

11.45 

11.70 

11.95 

12.  20 

12.  45 

12. 70 

12. 96 

13.21 

13. 46 

3.75 

11.00 

11.26 

11.51 

11.76 

12. 01 

12.  26 

12.  51 

12. 76 

13.02 

13.27 

13.52 

3.80 

11.06 

11.32 

11.57 

11.82 

12. 07 

12.  32 

12.  57 

12. 82 

13.08 

13.33 

13.58 

3.85 

11.12 

11.38 

11.63 

11.88 

12. 13 

12.  38 

12. 63 

12.  88 

13.14 

13.39 

13.64 

3.90 

11.18 

11.44 

11.69 

11.94 

12. 19 

12.  44 

12.69 

12. 94 

13.20 

13.45 

13. 70 

3.95 

11.24 

11.50 

11.75 

12. 00 

12.  25 

12.  50 

12. 75 

13.00 

13.26 

13.51 



13. 77 

4. 00 

11.30 

11.56 

11.81 

12.  06 

12.31 

12.  56 

12. 81 

13.06 

13. 32 

13.57 

13. 83 

4. 05 

11.36 

11.62 

11.87 

12. 12 

12.  37 

12.  62 

12.87 

13.12 

13.38 

13.63 

13.89 

4.10 

11.42 

11.68 

11.93 

12. 18 

12. 43 

12.  68 

12.  93 

13.18 

13.44 

13.69 

13.95 

4.15 

11.48 

11.74 

11.99 

12.  24 

12.  49 

12.  74 

12.99 

13.25 

13.50 

13.76 

14. 01 

4.  20 

11.54 

11.80 

12. 05 

12.  30 

12.  55 

12.80 

13.05 

13.31 

13.56 

13.82 

14.07 

4. 25 

11.60 

11.86 

12.11 

12.  36 

12. 61 

12.  86 

13.12 

13.  37 

13.62 

13.88 

14. 13 

4.30 

11.66 

11.92 

12. 17 

12. 42 

1-2. 67 

12. 92 

13.18 

13.43 

13.68 

13.94 

14. 19 

4. 35 

11.72 

11.98 

12.  23 

12. 48 

12. 73 

12. 98 

13  24 

13.49 

13. 74 

14.  00 

14.  25 

4.40 

11.78 

12.04 

12.29 

12.  54 

12. 79 

13.04 

13.30 

13.  55 

13.80 

14.06 

14. 31 

4. 45 

11.84 

12. 10 

12.35 

12. 60 

12.  85 

13.10 

13  36 

13.61 

13.86 

14. 12 

14. 37 

4.50 

11.90 

12. 16 

12. 41 

12. 66 

12. 91 

13.16 

13. 42 

13.67 

13.92 

14. 18 

14. 43 

4.  55 

11.97 

12. 22 

12. 47 

12. 72 

12.  97 

13.22 

13.48 

13.73 

13.98 

14.  24 

14.49 

4.60 

12. 03 

12.  28 

12.  53 

12. 78 

13.03 

13.28 

13.54 

13.79 

14. 04 

14. 30 

14. 55 

4.65 

12.09 

12. 34 

12.  59 

12. 84 

13.09 

13.34 

13.60 

13.85 

14. 10 

14. 36 

14. 61 

4.  70 

12. 15 

12.40 

12.  65 

12. 90 

13. 15 

13.40 

13.66 

13.91 

14. 16 

14. 42 

14.67 

4.75 

12.  21 

12. 46 

12.71 

12. 96 

13.21 

13.46 

13.72 

13.97 

14.  22 

14. 48 

14. 73 

4.80 

12.27 

12.52 

12. 77 

13.02 

13.27 

13.52 

13.78 

14.03 

14. 28 

14.54 

'.1.79 

4.85 

12.33 

12.58 

12.83 

13.08 

13.33 

13.58 

13.84 

14.09 

14.34 

14.60 

14.85 

4.90 

12. 39 

12.64 

12.89 

13.14 

13.39 

13. 64 

13.90 

14.15 

14.40 

14.66 

14.91 

4.95 

12.45 

12.70 

12.95 

13.20 

13. 45 

13.70 

13.96 

14.21 

14.46 

14.72 

14.97 

24 


ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


Table  15. — Table  for  determining  total  solids  in  milk  from  any  given  specijic  gravity 
and  percentage  of  fat — Continued. 


Per 


Lactometer  reading  at  60°  F.  (Quevenne  degrees). 


age  of 
fat. 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

Per 

cent 

cent 

cent 

cent 

cent 

total 

total 

total 

total 

total 

total 

total 

total 

total 

total 

total 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

solids. 

5. 00 

12. 51 

12. 76 

13. 01 

13. 26 

13. 51 

13. 76 

14.02* 

14. 27 

14. 52 

14. 78 

15. 03 

5.05 

12. 57 

12.82 

13. 07 

13. 32 

13. 57 

13. 83 

14.08 

14. 33 

14. 58 

14. 84 

15. 09 

5. 10 

12. 63 

12.88 

13. 13 

13.  38 

13. 63 

13. 89 

14. 14 

14. 39 

14. 64 

14. 90 

15. 15 

5. 15 

12. 69 

12!  94 

13. 19 

13.  44 

13.  69 

13. 95 

14. 20 

14. 45 

14. 70 

14. 96 

15. 21 

5. 20 

12!  75- 

13. 00 

13*  25 

13!  50 

13.  75 

14.01 

14!  26 

14!  51 

14. 76 

15. 02 

15. 27 

5. 25 

12. 81 

13. 06 

13!  31 

13. 56 

13. 81 

14. 07 

14.  32 

14.  57 

14^82 

15. 08 

15. 33 

5'  30 

12. 87 

13. 12 

13.37 

13. 62 

13. 87 

14. 13 

14.  38 

14. 63 

14.88 

15. 14 

15!  39 

5. 35 

12. 93 

13  18 

13. 43 

13. 68 

13. 93 

14. 19 

14.  44 

14.  70 

14. 95 

15. 20 

15. 45 

5^40 

12!  99 

13!  24 

13".  49 

13^74 

14!  00 

14!  25 

14^50 

14'.  76 

15^01 

15!  26 

15!  51 

5. 45 

13. 05 

13. 30 

13.55 

13.80 

14. 06 

14.31 

14.56 

14.82 

15. 07 

15. 32 

15. 57 

5. 50 

13. 11 

13.  36 

13. 61 

13.86 

14. 12 

14.  37 

14. 62 

14. 88 

15. 13 

15. 38 

15. 63 

5.  55 

13. 17 

13.  42 

13. 67 

13.  93 

14. 18 

14.  43 

14. 69 

14. 94 

15. 19 

15.  44 

15!  69 

5. 60 

13.  23 

13.  48 

13.  73 

13!  99 

14.  24 

14.  49 

14.  75 

15. 00 

15. 25 

15.  50 

15. 75 

5. 65 

13. 29 

13.  54 

13!  79 

14!  05 

14!  30 

14.  55 

14!  81 

15*06 

15!  31 

15.  56 

15. 81 

5. 70 

13. 35 

13. 60 

13. 85 

14. 11 

14.  36 

14.  61 

14. 87 

15. 12 

15. 37 

15. 62 

15. 87 

5. 75 

13.  41 

13.  66 

13. 91 

14. 17 

14. 42 

14.  68 

14. 93 

15. 18 

15.  43 

15. 68 

15. 93 

5. 80 

13.  47 

13. 72 

13.  97 

14.  23 

14.  48 

14. 74 

14.  99 

15. 24 

15.  49 

15.  74 

15. 99 

5. 85 

13.  53 

13  78 

14. 04 

14. 29 

14.  54 

14. 80 

15. 05 

15!  30 

15.  55 

15. 80 

16. 06 

5!  90 

13^59 

13^84 

14!  10 

14!  35 

14!  60 

14!  86 

15!  11 

15!  36 

15!  61 

15^86 

16!  12 

5. 95 

13. 65 

13.90 

14.16 

14. 41 

14.66 

14. 92 

15.17 

15.42 

15.  67 

15. 92 

16. 18 

6. 00 

13.  71 

13. 96 

14. 22 

14.  47 

14. 72 

14. 98 

15.23 

15. 48 

15.  73 

15. 98 

16. 24 

6. 05 

13.  77 

14. 02 

14!  28 

14!  53 

14. 78 

15.04 

15. 29 

15.  54 

15. 79 

16. 04 

16. 30 

6. 10 

13. 83 

14. 08 

14. 34 

14.  59 

14. 84 

15. 10 

15.  35 

15.  60 

15. 85 

16. 10 

16. 35 

6. 15 

13. 89 

14. 14 

14.  40 

14.  65 

14.  90 

15!  16 

15. 41 

15.  66 

15. 91 

16. 16 

16. 42 

6. 20 

13. 95 

14.  20 

14.  46 

14.  71 

14.  96 

15.22 

15. 47 

15.  72 

15. 97 

16^  22 

16.  48 

6. 25 

14. 01 

14.  26 

14.  52 

14.  77 

15. 02 

15.  28 

15.  53 

15.  78 

16. 03 

16. 28 

16.  54 

6. 30 

14. 07 

14!  32 

14.  58 

14. 83 

15. 08 

15.  34 

15.  59 

15. 84 

16.09 

16.  34 

16.  60 

6. 35 

14. 13 

14. 38 

14.  64 

14.  90 

15. 14 

15!  40 

15. 65 

15. 90 

16. 15 

16.  40 

16. 66 

6.40 

14!  19 

14!  44 

14!  70 

14!  96 

15. 20 

15!  46 

15!  71 

15!  96 

16!  21 

16!  46 

16!72 

6. 45 

14. 25 

14.50 

14.76 

15. 02 

15.  26 

15.52 

15. 77 

16.02 

16.  27 

16.52 

16. 78 

6.50 

14.31 

14.56 

14.82 

15.08 

15. 32 

15.58 

15.83 

16.08 

16. 33 

16.58 

16.84 

6.55 

14.37 

14.  62 

14.88 

15.14 

15.  38 

15.64 

15.89 

16.14 

16. 39 

16.64 

16.90 

6.60 

14.43 

14.68 

14. 94 

15. 20 

15.  44 

15.  70 

15.  95 

16. 20 

16. 45 

16.70 

16. 96 

6. 65 

14.  49 

14.  74 

15.00 

15.  26 

15.50 

1.5.  76 

16.01 

16. 26 

16. 51 

16. 76 

17.02 

6.70 

14.55 

14.80 

15.06 

15.  32 

15.  56 

15. 82 

16.07 

16. 32 

16. 57 

16.82 

17.08 

6. 75 

14.  61 

14. 86 

15.12 

15.  38 

15.  62 

15.88 

16. 13 

16.  38 

16.63 

16.88 

17.14 

6.80 

14.67 

14.92 

15.18 

15.  44 

15.68 

15.  94 

16.19 

16.  44 

16. 69 

16. 94 

17.20 

6.85 

14.  73 

14.  98 

15. 24 

15.50 

15.  74 

16.00 

16. 25 

16.50 

16. 75 

17.00 

17. 26 

6.  90 

14.  79 

15. 04 

15. 30 

15.  56 

15. 80 

16.06 

16.  31 

16. 56 

16.81 

17.06 

17.  32 

6.  95 

14.85 

15.10 

15.  36 

15. 62 

15. 86 

16.12 

16. 37 

16.62 

16.87 

17.12 

17.38 

PROPORTIONAL  PARTS. 


Lactometer 
fraction. 

Fraction  to 
be  added 
to  total 
solids. 

Lactometer 
fraction. 

Fraction  to 
be  added 
to  total 
solids. 

Lactometer 
fraction. 

Fraction  to 
be  added 
to  total 
solids. 

0.1 

0. 03 

0.4 

0. 10 

0.7 

0. 18 

_  2 

.05 

.  5 

.13 

.8 

.20 

!3 

.08 

.6 

.15 

.9 

.23 

SUMMARY  AND  CONCLUSIONS. 


25 


SUMMARY  AND  CONCLUSIONS. 

1.  For  purposes  where  exact  percentages  of  total  solids  are  de- 
nianded  the  use  of  any  formula  will  not  fulfill  the  requirements. 

2.  Of  the  formulas  in  general  use  that  known  as  the  Babcock 
(revised)  formula  gave  results  closest  to  those  obtained  gravimetri- 
cally.  In  430  composite  samples  analyzed  for  total  solids  256,  or 
nearly  60  per  cent,  when  calculated  with  this  formula  agreed  within 
0.25  per  cent  of  the  figures  obtained  gravimetrically,  and  389,  or 
over  90  per  cent,  agreed  within  0.50  per  cent.  In  another  test  with 
84  samples  of  milk  obtained  from  four  individual  cows  under  official 
testing  conditions,  determinations  made  on  each  milking  showed  that 
the  total  solids  calculated  by  the  formula  in  53  cases,  or  63  per  cent 
of  the  total,  agreed  within  0.25  per  cent  of  the  gravimetrically  deter- 
mined figures;  and  in  78  cases,  or  93  per  cent  of  the  total,  they 
agreed  within  0.50  per  cent. 

3.  Neither  individuality  nor  breed  in  the  cows  seemed  to  exert  any 
notable  influence  upon  the  application  of  the  formulas. 

4.  The  Babcock  formula  may  be  safely  used  with  normal  milk 
where  only  comparatively  close  approximations  are  required.  It 
must  be  left  to  the  decision  of  those  in  need  of  such  figures  as  to 
whether  or  not  the  formula  will  fulfill  their  particular  requirement. 

5.  The  lactometers  in  common  use  for  determining  specific  gravity 
of  milk  are  not  sufficiently  sensitive  to  be  used  in  connection  with 
the  Babcock  fat  test  for  estimating  total  solids  in  milk  by  formula. 
A  modification  of  the  Quevenne  lactometer  was,  however,  devised 
which  was  found  to  yield  results  quite  as  accurate  as  those  obtained 
with  the  Westphal  balance  and  at  the  same  time  so  constructed  that 
it  may  be  used  successfully  by  those  unskilled  in  the  use  of  chemical 
apparatus. 


/ 


APPENDIX. 


Table  16. — Comparative  determinations  of  total  solids  in  milk. 


Test 
No. 

Cow 
No. 

gl  a  V 1  l/j' 

( Quevenne 
degrees). 

Fat. 

Total  solids. 

Gravi- 
metric. 

Babcock. 

Richmond. 

Fleisch- 
mann. 

Per  cent. 

Per  cent. 

Per  cent. 

PeT  cent. 

Per  cent: 

1 

4 

33.2 

5. 07 

14. 39 

11.  oo 

14.  51 

14.  6.5 

2 

4 

34.5 

4. 66 

14.  40 

11.  /iZ 

14. 40 

14.  48 

3 

4 

33.7 

5.06 

L't.  01 

11.  OU 

14. 63 

14.  70 

4 

4 

33.0 

4. 93 

1%.  41 

14  17 

^  A  07 
11.  Zl 

14.  43 

5 

4 

33.6 

4.  83 

14  18 

14  20 

1  A  07 
11.  Zl 

t  A  AR 
11.  10 

6 

4 

34.5 

4.  80 

14. 26 

1  A  QQ 

11.  oy 

14.  52 

14.  65 

7 

4 

34.0 

5.  02 

14.  31 

11.  oz 

1  4  AQ 
11.  00 

14.  79 

8 

4 

33.7 

4.  83 

1  Q  QQ 

1  A  00 
11.  zz 

1  A  O"? 
11.  Zl 

14.  48 

9 

4 

33.0 

5. 14 

11.  18 

14  42 

1  4  (;i 
11.  01 

14.  68 

10 

4 

34.0 

5.00 

1  A  11 
11.  11 

14  50 

1  4  AQ 
11.  Oo 

1  4  7A 

11.  113 

11 

4 

31.5 

4.97 

13. 98 

lo.  ol 

14.  02 

14. 10 

12 

4 

33.5 

4.68 

13.  85 

1  Q  QQ 

lo.  yy 

14. 15 

14.  25 

13 

4 

32.5 

4.  77 

16.  oo 

10.  oO 

1 A  no 

11.  \]Z 

14. 11 

14 

4 

33.0 

4.50 

1  Q  7ft 
lo.  (D 

10.  DO 

1  Q  7Q 

10.  /y 

13. 91 

15 

4 

32.2 

4.  38 

13.  48 

1  Q  Q1 
lo.  Ol 

13.  42 

13.  57 

16 

4 

33. 1 

4.  44 

13.  61 

1  ■}  AH 
lo.  DU 

13.  67 

13.  87 

17 

4 

33.0 

4. 26 

14. 23 

lo.  OO 

16.  00 

13.  63 

18 

4 

33.6 

4.  57, 

13. 96 

10.  OO 

11.  uo 

14. 15 

19 

4 

33.0 

4.  65 

1  Q  OQ 

lo.  zy 

1  Q  CQ 
10.  oo 

1  A  (Yi 
11.  Uo 

14.  09 

20 

4 

34.0 

4.  85 

14.  03 

1  A  QO 
11.  oZ 

14. 51 

14.  58 

21 

4 

34.0 

5. 15 

14.  70 

1  /I  AC 
l^t.  Do 

14.  87 

14. 94 

22 

4 

34.0 

4.82 

14.  55 

1  A  OS 
11.  Zo 

1  4  QQ 

11.  oy 

14.  55 

23 

•  4 

32.8 

5.  39 

14.  75 

1  il  A7 

1  4  C7 
11.  Ol 

14. 93 

24 

4 

34.0 

5.  68 

11.  oU 

1  t;  QO 
10.  oZ 

1 1;  47 

10.  11 

15.  58 

25 

4 

33.6 

5.  61 

15. 15 

15. 13 

15. 23 

15.  40 

26 

99 

33.3 

4. 37 

13. 09 

13. 57 

13. 79 

13.  83 

27 

99 

33.4 

4.55 

13.  54 

13. 81 

14. 03 

14.  07 

28 

99 

33.0 

4.  51 

13. 49 

13. 66 

13.  79 

13.  93 

29 

99 

34.0 

4.53 

13. 43 

13. 94 

14. 03 

14.  20 

30 

99 

32.6 

4.14 

12.  72 

13. 12 

13. 18 

13. 38 

31 

99 

32.3 

4. 50 

13.  20 

13. 48 

13. 66 

13.  74 

32 

99 

32.7 

3.86 

12.  87 

12.  81 

12.  94 

13.  07 

33 

99 

32.9 

4. 74 

13.  50 

13. 91 

14. 03 

14. 18 

34 

99 

32.4 

4. 50 

13. 04 

13.  50 

13. 66 

13.  76 

35 

99 

32.0 

4. 39 

12.  84 

13.  27 

13. 42 

13.  63 

36 

99 

33.0 

4.32 

12.  95 

13. 43 

13. 55 

13.  70 

37 

99 

32.7 

4. 31 

12.  88 

13.  35 

13.  42 

13. 61 

38 

99 

31.0 

4.  28 

12.  99 

12. 89 

13. 06 

13. 15 

39 

99 

31.8 

4. 32 

12. 87 

13. 13 

13. 30 

13. 40 

40 

99 

32.2 

4.23 

12^84 

13^13 

13!  18 

13^39 

41 

99 

30.5 

4.43 

12.90 

12. 94 

13. 05 

13.  20 

42 

99 

31.0 

3.90 

12.42 

12.43 

12. 58 

12.69 

43 

99 

31.0 

4.27 

13.04 

12. 87 

13.06 

13.14 

44 

99 

30.9 

3.93 

12.67 

12.44 

12.  58 

12.  70 

45 

99 

32.0 

4. 30 

12.50 

13. 16 

13.30 

13.  42 

46 

99 

33.0 

4. 42 

13. 13 

13.55 

13. 67 

13. 82 

47 

99 

33.0 

4.07 

12.95 

13.13 

13.31 

13.40 

48 

99 

34.0 

4. 37 

13. 13 

13.  74 

13. 91 

14. 01 

49 

99 

32.5 

4.  80 

13.34 

13. 89 

14.02 

14.15 

50 

99 

32.7 

4.  70 

13.66 

13. 82 

13.90 

14.08 

51 

99 

32.0 

4.63 

13.  26 

13.56 

13.66 

13. 82 

52 

99 

32.4 

4.  74 

13.  85 

13. 79 

13.90 

14. 05 

53 

99 

35.5 

4.71 

14. 00 

14.53 

14.64 

14.79 

54 

99 

34.5 

5.08 

14.  55 

14. 72 

14. 88 

14.  98 

55 

99 

32.5 

5.  .39 

14.66 

14.  59 

14. 74 

14. 86 

.56 

99 

34.0 

5.26 

14.83 

14.81 

14. 99 

15.08 

57 

99 

35.0 

5. 78 

15.32 

15. 69 

15.84 

15.  95 

58 

99 

36.0 

6.00 

15.61 

16.20 

16.32 

16.  46 

59 

99 

32.3 

5.42 

14. 85 

14.58 

14. 74 

14. 84 

60 

99 

34.6 

5.99 

15.89 

15.84 

15.96 

16. 10 

61 

99 

33.5 

6.15 

16.11 

15.76 

13.95 

16.02 

26 


APPENDIX. 


Table  16. — Comparative  determinations  of  total  solids  in  milk — Continued. 


Test 
No. 

Cow 
No. 

Specific 
gravity 
(Quevenne 
degrees). 

Fat. 

Total  solids. 

Gravi 

Babcock. 

Richmond. 

mann. 

PCT  C€7ltt 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

62 

99 

34. 9 

6. 07  ' 

16.  24 

16.01 

16.  20 

16. 27 

63 

118 

30. 0 

5.06 

13. 93 

13. 57 

13. 77 

13.83 

64 

118 

31. 0 

5. 10 

14. 19 

13.87 

14. 02 

14. 13 

65 

118 

29. 7 

5. 77 

14. 12 

14. 35 

14.48 

14.61 

66 

118 

32.0 

5. 58 

14. 55 

14. 70 

14. 86 

14. 96 

67 

118 

34. 0 

5. 80 

15. 10 

15. 46 

15.  59 

15. 72 

68 

118 

35. 0 

5. 60 

15. 40 

15. 47 

15. 60 

15. 73 

69 

118 

34. 5 

5.69 

15. 41 

15.  45 

15.  60 

15. 72 

70 

118 

34. 5 

5. 76 

15.  30 

15. 54 

15.  72 

15.80 

71 

118 

34. 2 

5. 44 

14.  71 

15. 08 

15. 11 

15. 34 

72 

118 

34.0 

5.86 

15.  28 

15. 53 

15.  71 

15. 80 

73 

118 

34.5 

5.87 

15.  49 

15. 67 

15. 84 

15. 93 

74 

118 

34.5 

6. 10 

15. 50 

15.  95 

16. 08 

16.  20 

75 

118 

35.0 

5.  95 

16. 12 

15. 89 

16.  08 

16. 15 

76 

118 

35.0 

5.  28 

15. 35 

15.  09 

15. 24 

15. 35 

77 

118 

34.0 

5.86 

15. 47 

15. 53 

15. 71 

15. 80 

78 

118 

35.0 

5. 37 

15. 36 

15. 19 

15. 36 

15. 46 

79 

118 

33.  8 

5.  41 

15.  20 

14.  94 

15. 11 

15. 21 

80 

118 

34.0 

4.89 

14. 55 

14. 37 

14.  51 

14. 63 

81 

118 

33.4 

4. 99 

14. 06 

14. 34 

14.  51 

14. 60 

82 

118 

32.0 

4.  51 

13. 98 

13. 41 

13.  54 

13. 68 

83 

118 

35.0 

4.  83 

14.  83 

14. 55 

14. 64 

14. 81 

84 

118 

34.2 

5. 00 

14.  53 

14. 55 

14. 63 

14. 81 

85 

118 

34.2 

4.61 

14. 33 

14. 08 

14. 15 

14. 35 

86 

118 

35.4 

5. 15 

14. 65 

15. 03 

15. 24 

15. 29 

87 

118 

35.0 

4.57 

14.  29 

14.  23 

14. 40 

14. 50 

88 

118 

35.0 

5.21 

14. 55 

15. 00 

15. 12 

15. 26 

89 

118 

36.0 

4.86 

14. 93 

14. 83 

15. 00 

15. 09 

90 

118 

34.5 

5. 54 

15. 25 

15. 27 

15. 36 

15.  54 

91 

118 

37.0 

5. 49 

15.  58 

15.  84 

15. 97 

16. 10 

92 

118 

35.0 

5. 74 

16. 30 

15. 64 

15.  72 

15. 90 

93 

118 

35.0 

5. 42 

15.  75 

15.  25 

15. 36 

15. 52 

94 

118 

39.5 

5. 14 

16. 26 

16. 04 

16. 14 

16. 30 

95 

118 

33.5 

6. 29 

16. 18 

15. 92 

16. 07 

16. 19 

96 

205 

34.0 

3. 19 

12. 08 

12. 33 

12. 47 

12. 59 

97 

205 

34.0 

2. 09 

11. 32 

11. 73 

11. 87 

11. 99 

98 

205 

34.0 

3.30 

10. 95 

12. 46 

12. 59 

12. 72 

99 

205 

34.0 

3. 05 

11. 88 

12. 16 

12. 35 

12. 42 

100 

205 

32.5 

3. 14 

11. 80 

11. 89 

11. 98 

12. 16 

101 

205 

33.0 

3.38 

11. 59 

12. 31 

12.  47 

12.  57 

102 

205 

31.4 

3.00 

11. 03 

11. 45 

11.  62 

11. 71 

103 

205 

32.0 

2.  81 

12. 00 

11. 37 

11.  50 

11. 64 

104 

205 

34.5 

3.01 

11. 07 

12. 24 

12. 36 

12. 60 

105 

205 

33.0 

3. 17 

11. 66 

12. 05 

12.  23 

12. 32 

106 

205 

31.  5 

3.07 

11. 46 

11. 56 

11. 74 

11. 82 

107 

205 

32.5 

3. 10 

11. 95 

11. 85 

11. 98 

12. 11 

108 

205 

33.0 

3. 10 

11. 64 

11. 97 

12. 11 

12. 23 

109 

205 

33.  5 

3.  58 

12.  45 

12. 67 

12. 83 

12. 93 

110 

205 

31.4 

3.  21 

11. 76 

11. 70 

11. 86 

11. 97 

111 

205 

32. 1 

3. 33 

12. 20 

12. 02 

12. 10 

12.  29 

112 

205 

31.2 

3.34 

11. 95 

11. 81 

11. 86 

12. 07 

113 

205 

32.5 

3.32 

11. 96 

12. 11 

12. 22 

12. 37 

114 

205 

34.0 

3. 17 

12. 34 

12. 30 

12. 47 

12.  57 

115 

205 

33.7 

3.01 

11. 66 

12. 04 

12. 11 

12. 30 

116 

205 

32.8 

3.30 

11. 70 

12. 16 

12. 35 

12. 42 

117 

205 

33.0 

2. 87 

11.  77 

11.69 

11. 87 

11. 96 

118 

205 

32.5 

3.06 

11. 96 

11. 80 

11. 98 

12. 06 

119 

205 

33.0 

3.  54 

12. 19 

12.  50 

12. 59 

12. 76 

120 

205 

32.0 

3.  21 

11. 76 

11. 85 

11. 98 

12. 12 

121 

205 

32.0 

3.38 

12. 13 

12. 06 

12. 22 

12. 32 

122 

205 

34.0 

2.89 

11. 83 

11. 97 

12. 11 

12. 23 

123 

205 

33.0 

3.26 

11. 99 

12. 16 

12. 35 

12. 43 

124 

205 

32.7 

3. 19 

12. 10 

12. 00 

12. 10 

12. 27 

125 

205 

32^7 

3.38 

12. 25 

12. 23 

12. 34 

12. 50 

126 

205 

34. 6 

3. 15 

12. 31 

12. 43 

12. 60 

12. 69 

127 

205 

33!  6 

3. 17 

12. 06 

12. 20 

12. 35 

12. 47 

128 

205 

32. 5 

3. 28 

12^04 

12!  06 

12!  22 

12!  33 

129 

205 

33. 0 

2. 94 

11.74 

11.78 

11.87 

12.04 

130 

205 

32!  5 

3!  23 

12.01 

12.00 

12. 10 

12.27 

131 

205 

32.2 

3.36 

'  12.10 

12.08 

12.22 

12.35 

132 

205 

31.7 

3.38 

12. 15 

11.98 

12. 10 

12.  24 

133 

205 

32.5 

3.26 

12.20 

12.04 

12.22 

12.30 

134 

205 

33.0 

3.25 

11.90 

12. 15 

12.35 

12.41 

135 

205 

33.0 

3.27 

12.27 

12. 17 

12. 35 

12. 44 

136 

205 

33.7 

3.22 

12.42 

12.29 

12.35 

12.55 

137 

205 

32.0 

3.50 

12.19 

12. 20 

12.34 

12.  64 

138 

205 

33.5 

3.74 

12. 71 

12.86 

12.95 

13. 13 

ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


Table  16. — Comparative  determinations  of  total  solids  in  milk — Continued. 


Test 
No. 

Cow 
No. 

Specific 
gravity 
(Quevenne 
degrees). 

Fat. 

Total  solids. 

Gravi- 
metric. 

Babcock. 

Richmond. 

Fleisch- 
mann. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

139 

205 

33. 6 

3. 20 

12.  70 

12. 24 

12.35 

12.50 

140 

205 

33.5 

3. 63 

12.  96 

12. 73 

12.83 

12.99 

141 

205 

33. 4 

3. 40 

11.64 

12. 43 

12.59 

12.84 

142 

205 

32. 6 

3. 82 

12. 99 

12. 73 

12.82 

13.00 

143 

206 

31. 5 

3. 48 

11.97 

12.05 

12.22 

12.31 

144 

206 

29.0 

3. 17 

11.04 

11.05 

11.24 

11.32 

145 

206 

28.  2 

2. 58 

9. 95 

10. 15 

10.27 

10. 41 

146 

206 

29. 0 

3. 06 

10.  84 

10. 92 

11.12 

11.18 

147 

206 

29. 2 

2. 63 

10. 10 

10.  46 

10. 52 

10.72 

148 

206 

29.0 

2.  76 

10. 04 

10. 56 

10.76 

10.82 

149 

206 

29. 0 

2. 29 

9. 62 

10.00 

10. 16 

10.26 

150 

206 

29. 5 

2. 70 

11.02 

10. 62 

10.76 

10.88 

151 

206 

30. 0 

2. 58 

10.04 

10.60 

10.77 

10.86 

152 

206 

27. 5 

2. 94 

10.  23 

10.40 

10.51 

10. 66 

153 

206 

28. 2 

2.76 

9.99 

10. 36 

10.51 

10.62 

154 

206 

27. 5 

2. 96 

10. 27 

10.43 

10.63 

10.69 

155 

206 

29. 0 

2. 71 

10.57 

10.50 

10.64 

10. 76 

156 

206 

30. 0 

3. 10 

10.57 

11.22 

11.37 

11.48 

157 

206 

30. 0 

2. 72 

10. 43 

10. 76 

10.89 

11.03 

158 

206 

29. 0 

2. 94 

10. 67 

10. 78 

10.88 

11.04 

159 

206 

29. 0 

2.  78 

10.49 

10.59 

10.76 

10.85 

160 

206 

29. 0 

3. 06 

10.40 

10. 92 

11.12 

11.18 

161 

206 

30. 0 

3. 13 

10.  86 

11.26 

11.37 

11.52 

162 

206 

27.  8 

3. 01 

10.80 

10.56 

10. 75 

10.82 

163 

206 

28.  6 

3. 05 

10. 87 

10. 81 

10.99 

11.07 

164 

206 

28. 1 

3. 05 

10.  82 

10. 69 

10.87 

10. 94 

165 

206 

29. 0 

3. 08 

10.83 

10.95 

11.12 

11.21 

166 

206 

29. 0 

3. 01 

10. 92 

10.86 

11.00 

11.12 

167 

206 

29. 0 

2. 39 

10.  44 

10.12 

10. 28 

10.38 

168 

206 

29. 5 

3. 08 

10. 03 

11.07 

11.24 

11.33 

169 

206 

29. 0 

2. 86 

10. 71 

10.68 

10.88 

10. 94 

170 

206 

29. 0 

2. 82 

11.00 

10. 03 

10. 76 

10.90 

171 

206 

29. 0 

3. 23 

10. 85 

11.13 

11.24 

11.39 

172 

206 

29. 5 

3. 09 

10. 87 

11.08 

11.24 

11.34 

173 

206 

29.  3 

3. 13 

11.05 

11.08 

11.  24 

11. 34 

174 

206 

31. 0 

2.  70 

10. 93 

10. 99 

11.14 

11.25 

175 

206 

31. 0 

3. 06 

11.19 

11.42 

11.62 

11.69 

176 

206 

30. 0 

2.  93 

11.28 

11.02 

11.13 

11.28 

177 

206 

31.  0 

3. 35 

12. 10 

11.77 

11.98 

12.03 

178 

206 

32. 6 

3.03 

12. 18 

11.79 

11.86 

12.05 

179 

206 

32.  4 

3. 03 

12.03 

11.74 

11.86 

12.00 

180 

206 

33.  8 

3. 39 

12. 87 

12.52 

12. 71 

12.78 

181 

206 

34. 3 

3.  44 

13.09 

12. 70 

12. 84 

12.97 

L82 

206 

35.  3 

3.  40 

13.09 

12.91 

13.08 

13. 17 

183 

209 

31. 0 

3. 95 

12. 84 

12.49 

12.70 

12.75 

184 

209 

32. 0 

3. 14 

11.23 

11.77 

11.86 

12.03 

185 

209 

.32. 0 

2.59 

10.  44 

11.11 

11.26 

11.37 

186 

209 

32. 0 

2. 80 

10.  45 

11.36 

11.50 

11.62 

187 

209 

32. 0 

2.  40 

10.20 

10.88 

11.02 

11.14 

188 

209 

30.  0 

2.  64 

10. 09 

10. 67 

10.77 

10. 93 

189 

209 

30. 0 

2. 68 

10. 22 

10.72 

10.89 

10.98 

190 

209 

29. 8 

2.  67 

10.41 

10.65 

10.89 

10.92 

191 

209 

29. 0 

2. 54 

10. 99 

10.30 

10.40 

10.56 

192 

209 

30. 3 

2. 72 

10.21 

10.84 

11.01 

11.10 

193 

209 

31. 0 

2.96 

10.  63 

11.30 

11.50 

11.57 

194 

209 

29. 5 

2. 72 

10. 70 

10.04 

10.76 

10.90 

195 

209 

30.  5 

3.00 

10. 77 

11.23 

11.37 

11.49 

196 

209 

31.  5 

3.09 

11.39 

11.58 

11.74 

11.85 

197 

209 

28.  5 

2.96 

11.04 

10.68 

10.87 

10. 94 

198 

209 

28.  6 

3.00 

10.81 

10.75 

10.87 

11.01 

199 

209 

29.8 

3. 14 

11.18 

11.22 

11.37 

11.48 

200 

209 

29.5 

3.35 

11.21 

11.40 

11.60 

11.66 

201 

209 

31. 0 

3.05 

11.41 

11.41 

11.62 

11.67 

202 

209 

30.8 

2. 54 

10.81 

10.75 

10.90 

11.01 

203 

209 

31. 0 

3.24 

11.  46 

11.64 

11.74 

11.90 

204 

209 

30. 0 

2.  73 

10. 93 

10. 78 

10.89 

11.04 

205 

209 

29.  5 

2. 74 

10.62 

10.66 

10. 76 

10. 92 

206 

209 

30.5 

3.00 

11.20 

11.23 

11.37 

11.49 

207 

zuy 

oU.  u 

2. 95 

10.97 

11.04 

11.25 

11.30 

208 

209 

30.0 

3.08 

llr44 

11.20 

11.37 

11.40 

209 

209 

31.4 

2. 72 

11.20 

11.11 

11.26 

11.38 

210 

209 

31.0 

3. 15 

11.34 

11.53 

11.74 

11.79 

211 

209 

29.8 

2. 95 

10.87 

10.99 

11.25 

11.25 

212 

209 

30.9 

3.08 

11.39 

11.42 

11.62 

11.68 

213 

209 

30.7 

2. 87 

11.30 

11.12 

11.25 

11.38 

214 

209 

31.5 

2.94 

11.53 

11.40 

11.50 

11.67 

215 

209 

31.5 

3.06 

11.57 

11.55 

11.74 

11. SI 

APPENDIX. 


Table  16. — Comparative  determinations  of  total  solids  in  mi^^— Continued . 


Test 
No. 

Cow 
No. 

Specific 
gravity 
(Quevenne 
degrees). 

Total  solids. 

Gravi- 
metric. 

Ricliiiiond. 

Fleisch- 
mann. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

216 

209 

31.0 

3. 18 

11.59 

11.57 

11.74 

11.83 

217 

209 

31.3 

2.85 

11.62 

11.25 

11.50 

11.51 

218 

209 

31.3 

3.69 

12.49 

12.25 

12. 46 

12. 52 

219 

209 

32.2 

3.75 

12.68 

12.55 

12.62 

12.81 

220 

209 

33.0 

3.32 

12.  61 

12.23 

12.35 

12. 50 

221 

209 

33.3 

3.  33 

12.53 

12.32 

12.47 

12. 58 

222 

209 

32.6 

3.29 

12.28 

12.10 

12. 22 

12.36 

223 

209 

33.5 

3.27 

12. 76 

12.30 

12.47 

12. 56 

224 

209 

35.6 

3.52 

13.20 

13. 12 

13.20 

13.39 

225 

209 

36.0 

3.  74 

13.70 

13.49 

13.56 

13.75 

226 

209 

34.  4 

3.75 

13. 70 

13.10 

13.25 

13. 36 

227 

209 

37.0 

3.76 

13.98 

13.76 

13.93 

14  02 

228 

209 

34.4 

4.05 

13. 56 

13. 46 

13.68 

13.72 

229 

300 

33.0 

5. 19 

14  53 

14  48 

14  63 

14  74 

230 

300 

33.3 

4. 54 

13.76 

13.77 

13.91 

14. 04 

231 

300 

33.  4 

4. 18 

13.76 

13.37 

13.55 

13.63 

232 

300 

33.5 

4.  49 

13.94 

13.76 

13.91 

14  03 

233 

300 

33.  4 

4.38 

13.93 

13.61 

13.79 

13.87 

234 

300 

33.5 

4.22 

13.51 

13.  44 

13.55 

13. 70 

235 

300 

33.5 

4. 46 

13.42 

13.73 

13.91 

13.99 

236 

300 

33. 1 

4.07 

13. 76 

13. 16 

13.31 

13.42 

237 

300 

33.7 

4. 23 

13.53 

13.50 

13.55 

13.76 

238 

300 

33.6 

4.22 

13.53 

13.46 

13.55 

13.73 

239 

300 

33.5 

4.05 

13.41 

13.24 

13.  43 

13.  50 

240 

300 

33. 7 

4.01 

13.20 

13.24 

13.31 

13.50 

241 

300 

33.0 

4. 16 

13.24 

13.24 

13.43 

13.51 

242 

300 

32. 8 

4. 08 

13.39 

13.10 

13. 31 

13. 36 

243 

300 

32. 7 

4. 11 

13.44 

13.11 

13. 18 

13. 37 

244 

300 

32.  4 

3.  98 

13.  26 

12.88 

13.06 

13.  14 

245 

300 

32.  6 

3.  55 

12.  89 

12.  41 

12.  58 

12.  67 

246 

300 

32.  0 

4. 13 

13.  42 

12.  96 

13.06 

13.  22 

247 

300 

31.  8 

4  29 

13. 13 

13. 10 

13.  30 

13.  36 

248 

300 

32.  0 

4.  20 

12.  69 

13.  04 

13. 18 

13.  30 

249 

300 

34.  0 

4. 10 

13.  04 

13.42 

13.  55 

13.  68 

250 

300 

33.  4 

4.  12 

13.  07 

13.29 

13.  43 

13.  56 

251 

300 

34  0 

4.  02 

13.  44 

13.  32 

13.  43 

13.59 

252 

300 

35.  0 

4. 13 

13.  40 

13.  71 

13.  80 

13.  97 

253 

300 

35.  0 

4.  22 

13. 13 

13.  81 

13.  92 

14  08 

254 

300 

35.  0 

4.  08 

13.  34 

13.  65 

13.  80 

13.  91 

255 

300 

34.  0 

4. 17 

13.76 

13.  50 

13.  67 

13.  77. 

256 

300 

33.  0 

4.  32 

13.  39 

13.43 

13.  55 

13.  70 

257 

300 

33.  0 

3.  89 

12.  56 

12.92 

13.  07 

13. 18 

258 

300 

31.  5 

3.  65 

12.  57 

12.26 

12.46 

12.  52 

259 

300 

33.  0 

3.  22 

12.  04 

12. 11 

12.  23 

12.  38 

260 

300 

32.  0 

3.  94 

12.  40 

12.73 

12.  82 

12.  99 

261 

300 

33.  0 

3.  65 

12.  35 

12.  63 

12.  83 

12.89 

262 

300 

32. 0 

3.  61 

12.  28 

12.  33 

12.46 

12.  60 

263 

300 

32.  5 

3.  31 

12. 13 

.    12. 10 

12.  22 

12.  36 

264 

300 

32.  9 

3.  37 

12.  28 

12.  27 

12.  47 

12.  53 

265 

300 

33.  0 

3.  45 

12. 17 

12.39 

12.59 

12.65 

266 

300 

32.  0 

3.  38 

11.98 

12.  06 

12.  22 

12.  32 

267 

300 

31.  4 

3.  36 

12.  07 

11.  88 

12. 10 

12. 15 

268 

300 

30.  2 

3.  50 

11.  89 

11.  75 

11.85 

12.  01 

269 

300 

31.  2 

3.  23 

11.  70 

11.  68 

11.  74 

11.  94 

270 

300 

30.  5 

3.  35 

11.  57 

11.  65 

11.  85 

11.91 

271 

300 

30.  4 

3. 15 

11.  58 

11.  38 

11.  61 

11.  64 

272 

300 

31.  3 

3.  47 

11.  96 

11.99 

12.  22 

12.  25 

273 

300 

32.  0 

3.  30 

11.  70 

11.  96 

12.10 

12.22 

274 

300 

31.  6 

3.  35 

11.  38 

11.  92 

12. 10 

12.18 

275 

300 

30. 1 

3.  44 

11.  26 

11.  65 

11.  73 

11.  92 

276 

300 

31.  0 

3.  40 

11.  38 

11.  83 

11.  98 

12.09 

277 

300 

30.  2 

2.  98 

11.40 

11. 13 

11.  25 

11.39 

278 

300 

30.  2 

3.  20 

11.34 

11.  39 

11.49 

11.  65 

279 

301 

34.  0 

4.  22 

13.  38 

13.  56 

13.  67 

13.  83 

280 

301 

33.  0 

4. 15 

13.43 

13.  23 

13.  43 

13.49 

281 

301 

32.  3 

4.  66 

13.  55 

13. 67 

13.  90 

13.  93 

282 

301 

32.  0 

4.  44 

13.  43 

13.  33 

13.42 

13.59 

283 

301 

33. 0 

4.  29 

13.  41 

13.40 

13.  55 

13.  66 

284 

301 

32  4 

4  72 

13.  44 

13.  76 

13.  90 

14  03 

285 

301 

32!  9 

4  22 

13.  36 

13.29 

13.43 

13.  55 

286 

301 

32.5 

4  37 

13.  35 

13. 37 

13.  54 

13. 63 

287 

301 

32.8 

4  61 

13.  51 

13.73 

13.  91 

14  00 

288 

301 

31.5 

4  72 

13.  78 

13. 54 

13.  66 

13.  80 

289 

301 

34.2 

416 

12.  98 

13.54 

13.  67 

13.  81 

290 

301 

33.2 

4  40 

13.  33 

13.58 

13.  67 

13.  84 

291 

301 

32.2 

4  31 

13.  54 

13.  22 

13.  30 

13.  49 

292 

301 

33.0 

442 

13. 67 

13.55 

13.67 

13.82 

ESTIMATION  OF  TOTAL  SOLIDS  IN  MILK. 


Table  16. — Comparative  determinations  of  total  solids  in  milk — Continued, 


Test 
No. 

Cow 
No. 

Specific 
gravity 
(Quevenne 
degrees). 

Fat. 

Total  solids. 

Gravi- 
metric. 

Babcock. 

Richmond. 

Fleisch- 
mann. 

Jr^CT  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

293 

301 

66.  7 

4.  02 

13.  47 

13.  25 

13. 31 

13. 51 

294 

301 

OO.  0 

0  SQ 
6.  OO 

13.  41 

13.03 

13.19 

13.29 

/yo 

cSUi 

0%.  ii 

1  QO 

0.  yz 

13.  27 

13.  25 

13. 31 

13.52 

296 

301 

34.  0 

A  no 

13.99 

13.  41 

13.55 

13.67 

297 

301 

iA  n 
o4.  u 

A  OA 

13.31 

13.59 

13. 67 

13.85 

298 

301 

66.  o 

A  on 

12.83 

13.42 

13. 55 

13.68 

301 

OO.  u 

A  1A 

13.37 

13.46 

13.55 

13.72 

300 

301 

OO.  u 

3  72 

12.91 

12. 71 

12.83 

12.98 

301 

301 

11  n 

OO.  u 

4.  zo 

13.46 

13.33 

13.43 

13.59 

302 

301 

iA  n 
6%.  u 

£iO 

13.36 

13.60 

13.79 

13.86 

303 

301 

11  n 

OO.  tl 

4  32 

13.23 

13.43 

13.55 

13.70 

304 

301 

OO.  o 

/«  1 1 

4.  11 

13. 71 

13. 81 

13. 92 

14.07 

305 

301 

34. 0 

O  CQ 

0.  oy 

13. 34 

13. 17 

13.31 

13.43 

306 

301 

34. 0 

0  t;R 

O.  00 

12. 94 

12. 77 

12. 95 

13.04 

307 

301 

11  k; 

OO.  0 

0  on 
o.  yu 

12.80 

13.06 

13. 19 

13.32 

308 

301 

34. 0 

O  QC 

o.  yo 

13.02 

13. 28 

13.43 

13.54 

309 

301 

61.  1 

o  t;c 
o.  08 

12.54 

12.  22 

12.34 

12.48 

310 

301 

Ol.  1 

o"  ^? 

12.37 

12.  20 

12. 34 

12. 47 

311 

301 

33. 8 

3.  71 

12.05 

12.  90 

13.07 

13.17 

312 

301 

32. 0 

3.  75 

12.36 

12.50 

12.70 

12.76 

313 

301 

33. 0 

3. 83 

12. 61 

12.85 

12. 95 

13.11 

314 

301 

in  K 
o/.  o 

3. 80 

12.64 

12.69 

12.82 

12. 95 

315 

301 

33.  0 

3. 85 

12.66 

12.87 

13.07 

13. 13 

316 

301 

32. 0 

O  71 
0.  /I 

12.  74 

12.45 

12.58 

12.  72 

317 

301 

6Zi.  o 

O  7!i 
0.  /O 

12.67 

12.63 

12.82 

12.89 

318 

301 

32. 0 

4.  01 

12.80 

12.81 

12.94 

13.08 

319 

30l 

33. 0 

3. 75 

12.53 

12. 75 

12.95 

13.01 

320 

301 

32.  5 

4. 12 

13. 11 

13.07 

13. 18 

13.33 

321 

301 

32. 6 

3. 86 

12.93 

12.78 

12.94 

13. 05 

322 

301 

33. 6 

4. 24 

13. 31 

13.49 

13.55 

13.  75 

323 

301 

oZ.  i 

4. 09 

13.01 

13.01 

13. 18 

13. 27 

324 

301 

OO  fi 

4.  00 

12.74 

13.00 

13. 19 

13.26 

325 

301 

33. 6 

O  71 
O.  /I 

13.01 

12.85 

12.95 

13. 12 

326 

301 

32. 9 

3.  65 

12. 77 

12.61 

12.83 

12.87 

327 

301 

33. 0 

3.  76 

12.90 

12.76 

12.95 

13.03 

328 

301 

32.  6 

4. 07 

12.90 

13.03 

13. 18 

13.30 

329 

30l 

33. 0 

3.  77 

12.50 

12.77 

12.95 

13.04 

330 

301 

32. 1 

4. 00 

12. 26 

12.83 

12.94 

13.09 

331 

301 

32. 0 

3. 96 

12. 85 

12.75 

12.94 

13.02 

332 

301 

31. 2 

4. 16 

12. 38 

12.79 

12.94 

13  06 

333 

301 

31.  4 

3.  76 

12.  71 

12.36 

12.58 

12.63 

334 

301 

32. 7 

3.  76 

12.67 

12.69 

12.82 

12.95 

335 

301 

OO  K 

61.  o 

4. 07 

12.79 

13.01 

13. 18 

13.27 

336 

301 

32. 9 

O  KK 

o.  oO 

12.86 

12.49 

12. 71 

12. 75 

337 

301 

31.  5 

3. 84 

12. 16 

12.48 

12.58 

12. 75 

338 

301 

31. 3 

3. 61 

12.09 

12. 16 

12.34 

12. 42 

339 

301 

32. 5 

3. 67 

12. 84 

12.53 

12.70 

12.79 

340 

301 

31. 2 

O  71 

6.  11. 

12.  34 

12.25 

12. 34 

12.52 

341 

302 

31. 8 

4. 88 

13.98 

13.81 

14. 02 

14.07 

342 

302 

31. 0 

4.  73 

13.70 

13.43 

13.  54 

13.69 

343 

302 

32. 0 

3. 92 

12.80 

12.70 

12. 82 

12. 97 

344 

302 

01  R 
ol.  D 

4.  (Jo 

12.88 

12.80 

12.94 

13.06 

1AK 

o4o 

302 

OO  n 
Oil.  u 

4.  47 

12. 97 

13.36 

13.54 

13.63 

346 

302 

OO  Q 

o^.  y 

4  11 
4.  11 

12.52 

13. 16 

13.31 

13.42 

347 

302 

32. 8 

4.  48 

13.45 

13.58 

13.79 

13.84 

348 

302 

ol  & 

ol.  O 

4.  48 

13.31 

13. 33 

13.  54 

13.59 

349 

302 

ol 

ol.  D 

J  71 
4.  /  I 

13. 67 

13.55 

13. 66 

13.82 

ooU 

302 

OO  c 
6^.  o 

/(  A7 
4.  U/ 

12.87 

13.08 

13.31 

13.35 

OKI 

302 

31. 0 

/I  71 
4.  /I 

13.15 

13.40 

13.54 

13.67 

352 

302 

29.  5 

K   1  O 
0.  18 

13.54 

13.59 

13. 76 

13.85 

353 

400 

34. 5 

4.  48 

14. 16 

14.00 

14. 16 

14.26 

354 

400 

35. 5 

4. 07 

13.83 

13.76 

13.92 

14.02 

355 

400 

36.  0 

3.88 

13. 51 

13.66 

13.80 

13.92 

356 

400 

36. 0 

4. 03 

13.35 

13.84 

13.92 

14. 10 

357 

400 

34. 0 

4. 33 

13.58 

i3.ro 

13. 79 

13.96 

358 

400 

31. 3 

3.95 

13.25 

12. 57 

12.82 

12.83 

359 

400 

33. 7 

3. 92 

12.98 

13. 13 

13. 19 

13.39 

360 

400 

33.6 

4. 17 

13.  35 

13. 40 

13. 55 

13.67 

361 

400 

33. 0 

4  13 

13.  58 

13.21 

13. 31 

13.47 

362 

400 

3215 

4131 

13.23 

13. 30 

13.42 

13.56 

363 

400 

33.5 

3.99 

12. 87 

13. 16 

13.31 

13.43 

364 

400 

34.0 

3.54 

12.52 

12. 75 

12.83 

13.01 

365 

400 

32.0 

3.30 

12.05 

11.96 

12.10 

12.22 

366 

400 

33.0 

3.99 

12.81 

13.04 

13. 19 

13. 30 

367 

400 

34.0 

3.57 

12.11 

12.78 

12.95 

13. 05 

368 

400 

32.8 

3.73 

12.96 

12. 68 

12.83 

12.94 

369 

400 

33.1 

3.53 

12.91 

12.51 

12.71 

12.78 

APPENDIX. 


Table  16. — Comparative  determinations  of  total  solids  in  milk — Continued. 


Test 
No. 

Cow 
No. 

Specific 
gravity 
(Quevenne 
degrees). 

Fat. 

Total  solids. 

Gravi- 
metric. 

Babcock. 

Richmond. 

r  leiscn- 
mann. 

xCT  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

i7n 

O/U 

400 

ic;  1 
00.  L 

1  09 
0. 

13.28 

13.48 

13.56 

13. 74 

171 

400 

14  n 

3  78 

12.94 

13.04 

13. 19 

13.30 

372 

400 

It;  o 
oO.  u 

0. 00 

13.11 

13. 01 

13. 20 

13.27 

o/o 

400 

34  6 

3. 62 

13.17 

12.99 

13. 08 

13.26 

174 

400 

11  4 
00.  * 

3. 72 

13. 01 

12. 81 

12.95 

13.08 

375 

400 

33  7 

3. 61 

13. 01 

12. 76 

12.83 

13.02 

14  1 

o4. 0 

1  70 

0.  /y 

13.00 

13. 12 

13.32 

13.39 

Q77 
Oil 

4nn 

It;  o 
oo.  u 

1  e:9 
0.  0^ 

12. 69 

12. 97 

13.08 

13.24 

378 

400 

34.  0 

4. 07 

12.99 

13.38 

13. 55 

13.65 

Q7Q 

4nn 
^uu 

14  o 

oi.  u 

1  8"; 
0. 00 

13. 18 

13.12 

13. 31 

13.38 

Qfin 

OoU 

4nf» 

11  9 
00.  ^ 

1  ot; 
0.  yo 

12. 97 

13.04 

13. 19 

13. 30 

QOI 

ool 

Ann 

11  7 
00.  / 

3  53 

12. 88 

12.66 

12. 71 

12.92 

QQ9 
OO^ 

Ann 

14  4 
0^.  % 

3  90 

13.26 

13.28 

13.44 

13.54 

OOO 

Ann 

34  6 

3. 96 

13.34 

13.40 

13.56 

13.66 

OO^ 

Ann 

14  7 

3. 53 

12. 85 

12.94 

12.96 

13. 17 

OOO 

400 

32  6 

3.  43 

12.40 

12. 27 

12. 34 

12.53 

OOD 

Ann 

32  0 

3. 91 

13.03 

12. 69 

12.82 

12.96 

187 

Af\n 

34  0 

A.  52 

13.48 

13.92 

14.03 

14. 19 

OOO 

409 

36  0 

4.  49 

14.06 

14. 39 

14. 52 

14. 65 

180 

402 

35  0 

5. 14 

14. 32 

14.92 

15.00 

15. 18 

402 

32  9 

4.  48 

13.62 

13.60 

13.79 

13.87 

1Q1 

4n9 

32  6 

4. 08 

12. 94 

13.05 

13. 18 

13.31 

402 

32  8 

4. 31 

13. 18 

13. 37 

13.55 

13.64 

oyo 

402 

33  0 

4. 20 

13.34 

13.29 

13.43 

13.55 

394 

402 

34  5 

4. 20 

13.  41 

13. 67 

13. 80 

13.93 

iQt; 
oyo 

402 

34  0 

3. 96 

13.23 

13. 25 

13.43 

13.52 

396 

402 

34. 0 

4. 21 

13.46 

13.55 

13. 67 

13.82 

1Q7 

oy< 

402 

33  5 

3. 92 

12. 91 

13. 08 

13. 19 

13.34 

108 
oyo 

402 

32  5 

3. 77 

12.83 

12. 65 

12.82 

12.91 

100 

oyy 

402 

34. 0 

3. 99 

13.07 

13.29 

13.43 

13. 55 

400 

402 

33. 7 

3. 61 

12.  78 

12. 76 

12.83 

13.02 

401 

402 

34. 0 

4. 03 

13. 41 

13. 34 

13. 43 

13.60 

402 

402 

34. 4 

3. 69 

13.01 

13.03 

13. 20 

13.29 

403 

402 

34. 0 

3. 86 

13. 06 

13.13 

13.31 

13.40 

AHA 

4n9 

11  o 

oo.  u 

1  09 
0.  y^ 

13.06 

12. 95 

13. 07 

13.22 

405 

402 

34. 0 

3. 84 

13.26 

13.11 

13. 19 

13. 37 

406 

402 

34. 4 

3. 80 

13. 21 

13.16 

13. 32 

13.42 

407 

402 

33. 4 

3. 80 

13.11 

12.91 

13. 07 

13. 17 

408 

402 

33!  7 

3  yg 

13. 15 

12. 97 

13.07 

13. 24 

409 

402 

34. 0 

3. 93 

12. 94 

13.22 

13. 31 

13.48 

41  o 

409 

14  4 

1  78 
0.  10 

12. 86 

13.14 

13.32 

13.40 

41 1 

402 

11  fi 
00.  D 

4  Ifi 

12. 94 

13.39 

13. 55 

13.66 

412 

402 

19  7 
0^.  / 

3  94 

13.10 

12. 90 

12. 94 

13. 17 

411 
*iO 

409 

19  7 

4. 12 

12. 69 

13.12 

13.18 

13. 38 

41  4 

409 

11  4 
00.  ^ 

3. 76 

13.02 

12. 86 

13. 07 

13. 13 

no 

409 

14  1=; 
0*.  0 

4  no 
^.  uy 

13. 26 

13.53 

13.68 

13.80 

41 R 

402 

14  n 

O'i.  u 

4. 20 

13.46 

13. 54 

13.67 

13.80 

417 

401 

Wo 

35  8 

4  OR 

13.63 

13. 82 

14. 04 

14.08 

418 

401 

36. 0 

1  t;i 
0. 00 

12. 85 

13. 24 

13. 32 

13.50 

41 Q 

^ly 

403 

33. 8 

3  45 

12. 42 

12.59 

12. 83  . 

12.85 

401 

33. 4 

1  27 
0.  ^/ 

12.  49 

1  0  07 

12.  47 

12. 54 

491 

Ant 

33. 3 

1  It; 
0. 00 

12. 21 

12. 35 

12.59 

12.61 

422 

403 

32!  7 

3.35 

12. 07 

12. 20 

12. 34 

12.46 

423 

403 

33.3 

3. 45 

12. 12 

12.47 

12. 71 

12.  73 

424 

403 

32.0 

3.36 

12. 22 

12.03 

12. 22 

12. 30 

425 

403 

32.0 

3.33 

11.61 

12.00 

12. 10 

12. 26 

426 

403 

32.3 

2.96 

11.86 

11.63 

11.86 

11.89 

427 

403 

32.9 

3. 16 

11.53 

12.02 

12.23 

11.28 

428 

403 

33.6 

3.26 

12.00 

12. 31 

12. 47 

12.58 

429 

403 

32.3 

3.01 

11.32 

11.69 

11.86 

11.95 

430 

403 

31.6 

3. 19 

11.40 

11.73 

11.86 

11.99 

Note.— Cows  Nos.  4,  99,  and  118  are  Jerseys;  Nos.  205,  206,  and  209  are  Holstein- 
Friesians;  Nos.  300,  301,  and  302  are  Ayrshires,  and  Nos.  400,  402,  and  403  are  Shorthorns. 


O 


